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Semi-raw execution of a matlab command. Smartly handle calls to matlab, figure out what to do with `args`, and when to use function call syntax and not. If no `args` are specified, the ``cmd`` not ``result = cmd()`` form is used in Matlab -- this also makes literal Matlab commands legal (eg. cmd=``get(gca, 'Children')``). If ``nout=0`` is specified, the Matlab command is executed as procedure, otherwise it is executed as function (default), nout specifying how many values should be returned (default 1). **Beware that if you use don't specify ``nout=0`` for a `cmd` that never returns a value will raise an error** (because assigning a variable to a call that doesn't return a value is illegal in matlab). ``cast`` specifies which typecast should be applied to the result (e.g. `int`), it defaults to none. XXX: should we add ``parens`` parameter? def _do(self, cmd, *args, **kwargs): """Semi-raw execution of a matlab command. Smartly handle calls to matlab, figure out what to do with `args`, and when to use function call syntax and not. If no `args` are specified, the ``cmd`` not ``result = cmd()`` form is used in Matlab -- this also makes literal Matlab commands legal (eg. cmd=``get(gca, 'Children')``). If ``nout=0`` is specified, the Matlab command is executed as procedure, otherwise it is executed as function (default), nout specifying how many values should be returned (default 1). **Beware that if you use don't specify ``nout=0`` for a `cmd` that never returns a value will raise an error** (because assigning a variable to a call that doesn't return a value is illegal in matlab). ``cast`` specifies which typecast should be applied to the result (e.g. `int`), it defaults to none. XXX: should we add ``parens`` parameter? """ handle_out = kwargs.get('handle_out', _flush_write_stdout) #self._session = self._session or mlabraw.open() # HACK if self._autosync_dirs: mlabraw.eval(self._session, "cd('%s');" % os.getcwd().replace("'", "''")) nout = kwargs.get('nout', 1) #XXX what to do with matlab screen output argnames = [] tempargs = [] try: for count, arg in enumerate(args): if isinstance(arg, MlabObjectProxy): argnames.append(arg._name) else: nextName = 'arg%d__' % count argnames.append(nextName) tempargs.append(nextName) # have to convert these by hand ## try: ## arg = self._as_mlabable_type(arg) ## except TypeError: ## raise TypeError("Illegal argument type (%s.:) for %d. argument" % ## (type(arg), type(count))) mlabraw.put(self._session, argnames[-1], arg) if args: cmd = "%s(%s)%s" % (cmd, ", ".join(argnames), ('',';')[kwargs.get('show',0)]) # got three cases for nout: # 0 -> None, 1 -> val, >1 -> [val1, val2, ...] if nout == 0: handle_out(mlabraw.eval(self._session, cmd)) return # deal with matlab-style multiple value return resSL = ((["RES%d__" % i for i in range(nout)])) handle_out(mlabraw.eval(self._session, '[%s]=%s;' % (", ".join(resSL), cmd))) res = self._get_values(resSL) if nout == 1: res = res[0] else: res = tuple(res) if kwargs.has_key('cast'): if nout == 0: raise TypeError("Can't cast: 0 nout") return kwargs['cast'](res) else: return res finally: if len(tempargs) and self._clear_call_args: mlabraw.eval(self._session, "clear('%s');" % "','".join(tempargs))
r"""Directly access a variable in matlab space. This should normally not be used by user code. def _get(self, name, remove=False): r"""Directly access a variable in matlab space. This should normally not be used by user code.""" # FIXME should this really be needed in normal operation? if name in self._proxies: return self._proxies[name] varname = name vartype = self._var_type(varname) if vartype in self._mlabraw_can_convert: var = mlabraw.get(self._session, varname) if isinstance(var, ndarray): if self._flatten_row_vecs and numpy.shape(var)[0] == 1: var.shape = var.shape[1:2] elif self._flatten_col_vecs and numpy.shape(var)[1] == 1: var.shape = var.shape[0:1] if self._array_cast: var = self._array_cast(var) else: var = None if self._dont_proxy.get(vartype): # manual conversions may fail (e.g. for multidimensional # cell arrays), in that case just fall back on proxying. try: var = self._manually_convert(varname, vartype) except MlabConversionError: pass if var is None: # we can't convert this to a python object, so we just # create a proxy, and don't delete the real matlab # reference until the proxy is garbage collected var = self._make_proxy(varname) if remove: mlabraw.eval(self._session, "clear('%s');" % varname) return var
r"""Directly set a variable `name` in matlab space to `value`. This should normally not be used in user code. def _set(self, name, value): r"""Directly set a variable `name` in matlab space to `value`. This should normally not be used in user code.""" if isinstance(value, MlabObjectProxy): mlabraw.eval(self._session, "%s = %s;" % (name, value._name)) else: ## mlabraw.put(self._session, name, self._as_mlabable_type(value)) mlabraw.put(self._session, name, value)
Dispatches the matlab COM client. Note: If this method fails, try running matlab with the -regserver flag. def open(self, visible=False): """ Dispatches the matlab COM client. Note: If this method fails, try running matlab with the -regserver flag. """ if self.client: raise MatlabConnectionError('Matlab(TM) COM client is still active. Use close to ' 'close it') self.client = win32com.client.Dispatch('matlab.application') self.client.visible = visible
Evaluates a matlab expression synchronously. If identify_erros is true, and the last output line after evaluating the expressions begins with '???' an excpetion is thrown with the matlab error following the '???'. The return value of the function is the matlab output following the call. def eval(self, expression, identify_erros=True): """ Evaluates a matlab expression synchronously. If identify_erros is true, and the last output line after evaluating the expressions begins with '???' an excpetion is thrown with the matlab error following the '???'. The return value of the function is the matlab output following the call. """ #print expression self._check_open() ret = self.client.Execute(expression) #print ret if identify_erros and ret.rfind('???') != -1: begin = ret.rfind('???') + 4 raise MatlabError(ret[begin:]) return ret
Loads the requested variables from the matlab com client. names_to_get can be either a variable name or a list of variable names. If it is a variable name, the values is returned. If it is a list, a dictionary of variable_name -> value is returned. If convert_to_numpy is true, the method will all array values to numpy arrays. Scalars are left as regular python objects. def get(self, names_to_get, convert_to_numpy=True): """ Loads the requested variables from the matlab com client. names_to_get can be either a variable name or a list of variable names. If it is a variable name, the values is returned. If it is a list, a dictionary of variable_name -> value is returned. If convert_to_numpy is true, the method will all array values to numpy arrays. Scalars are left as regular python objects. """ self._check_open() single_itme = isinstance(names_to_get, (unicode, str)) if single_itme: names_to_get = [names_to_get] ret = {} for name in names_to_get: ret[name] = self.client.GetWorkspaceData(name, 'base') # TODO(daniv): Do we really want to reduce dimensions like that? what if this a row vector? while isinstance(ret[name], (tuple, list)) and len(ret[name]) == 1: ret[name] = ret[name][0] if convert_to_numpy and isinstance(ret[name], (tuple, list)): ret[name] = np.array(ret[name]) if single_itme: return ret.values()[0] return ret
Loads a dictionary of variable names into the matlab com client. def put(self, name_to_val): """ Loads a dictionary of variable names into the matlab com client. """ self._check_open() for name, val in name_to_val.iteritems(): # First try to put data as a matrix: try: self.client.PutFullMatrix(name, 'base', val, None) except: self.client.PutWorkspaceData(name, 'base', val)
Opens MATLAB using specified connection (or DCOM+ protocol on Windows)where matlab_location def open(): global _MATLAB_RELEASE '''Opens MATLAB using specified connection (or DCOM+ protocol on Windows)where matlab_location ''' if is_win: ret = MatlabConnection() ret.open() return ret else: if settings.MATLAB_PATH != 'guess': matlab_path = settings.MATLAB_PATH + '/bin/matlab' elif _MATLAB_RELEASE != 'latest': matlab_path = discover_location(_MATLAB_RELEASE) else: # Latest release is found in __init__.by, i.e. higher logical level raise MatlabReleaseNotFound('Please select a matlab release or set its location.') try: ret = MatlabConnection(matlab_path) ret.open() except Exception: #traceback.print_exc(file=sys.stderr) raise MatlabReleaseNotFound('Could not open matlab, is it in %s?' % matlab_path) return ret
Tries to guess matlab process release version and location path on osx machines. The paths we will search are in the format: /Applications/MATLAB_R[YEAR][VERSION].app/bin/matlab We will try the latest version first. If no path is found, None is reutrned. def _list_releases(): ''' Tries to guess matlab process release version and location path on osx machines. The paths we will search are in the format: /Applications/MATLAB_R[YEAR][VERSION].app/bin/matlab We will try the latest version first. If no path is found, None is reutrned. ''' if is_linux(): base_path = '/usr/local/MATLAB/R%d%s/bin/matlab' else: # assume mac base_path = '/Applications/MATLAB_R%d%s.app/bin/matlab' years = range(2050,1990,-1) release_letters = ('h', 'g', 'f', 'e', 'd', 'c', 'b', 'a') for year in years: for letter in release_letters: release = 'R%d%s' % (year, letter) matlab_path = base_path % (year, letter) if os.path.exists(matlab_path): yield (release, matlab_path)
Checks that the given version code is valid. def is_valid_release_version(version): '''Checks that the given version code is valid.''' return version is not None and len(version) == 6 and version[0] == 'R' \ and int(version[1:5]) in range(1990, 2050) \ and version[5] in ('h', 'g', 'f', 'e', 'd', 'c', 'b', 'a')
Tries to guess matlab's version according to its process path. If we couldn't gues the version, None is returned. def find_matlab_version(process_path): """ Tries to guess matlab's version according to its process path. If we couldn't gues the version, None is returned. """ bin_path = os.path.dirname(process_path) matlab_path = os.path.dirname(bin_path) matlab_dir_name = os.path.basename(matlab_path) version = matlab_dir_name if not is_linux(): version = matlab_dir_name.replace('MATLAB_', '').replace('.app', '') if not is_valid_release_version(version): return None return version
Opens the matlab process. def open(self, print_matlab_welcome=False): '''Opens the matlab process.''' if self.process and not self.process.returncode: raise MatlabConnectionError('Matlab(TM) process is still active. Use close to ' 'close it') self.process = subprocess.Popen( [self.matlab_process_path, '-nojvm', '-nodesktop'], stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.STDOUT) flags = fcntl.fcntl(self.process.stdout, fcntl.F_GETFL) fcntl.fcntl(self.process.stdout, fcntl.F_SETFL, flags| os.O_NONBLOCK) if print_matlab_welcome: self._sync_output() else: self._sync_output(None)
Evaluates a matlab expression synchronously. If identify_erros is true, and the last output line after evaluating the expressions begins with '???' and excpetion is thrown with the matlab error following the '???'. If on_new_output is not None, it will be called whenever a new output is encountered. The default value prints the new output to the screen. The return value of the function is the matlab output following the call. def eval(self, expression, identify_errors=True, print_expression=True, on_new_output=sys.stdout.write): """ Evaluates a matlab expression synchronously. If identify_erros is true, and the last output line after evaluating the expressions begins with '???' and excpetion is thrown with the matlab error following the '???'. If on_new_output is not None, it will be called whenever a new output is encountered. The default value prints the new output to the screen. The return value of the function is the matlab output following the call. """ self._check_open() if print_expression: print expression self.process.stdin.write(expression) self.process.stdin.write('\n') ret = self._sync_output(on_new_output) # TODO(dani): Use stderr to identify errors. if identify_errors and ret.rfind('???') != -1: begin = ret.rfind('???') + 4 end = ret.find('\n', begin) raise MatlabError(ret[begin:end]) return ret
Loads a dictionary of variable names into the matlab shell. oned_as is the same as in scipy.io.matlab.savemat function: oned_as : {'column', 'row'}, optional If 'column', write 1-D numpy arrays as column vectors. If 'row', write 1D numpy arrays as row vectors. def put(self, name_to_val, oned_as='row', on_new_output=None): """ Loads a dictionary of variable names into the matlab shell. oned_as is the same as in scipy.io.matlab.savemat function: oned_as : {'column', 'row'}, optional If 'column', write 1-D numpy arrays as column vectors. If 'row', write 1D numpy arrays as row vectors. """ self._check_open() # We can't give stdin to mlabio.savemat because it needs random access :( temp = StringIO() mlabio.savemat(temp, name_to_val, oned_as=oned_as) temp.seek(0) temp_str = temp.read() temp.close() self.process.stdin.write('load stdio;\n') self._read_until('ack load stdio\n', on_new_output=on_new_output) self.process.stdin.write(temp_str) #print 'sent %d kb' % (len(temp_str) / 1024) self._read_until('ack load finished\n', on_new_output=on_new_output) self._sync_output(on_new_output=on_new_output)
Loads the requested variables from the matlab shell. names_to_get can be either a variable name, a list of variable names, or None. If it is a variable name, the values is returned. If it is a list, a dictionary of variable_name -> value is returned. If it is None, a dictionary with all variables is returned. If extract_numpy_scalars is true, the method will convert numpy scalars (0-dimension arrays) to a regular python variable. def get(self, names_to_get, extract_numpy_scalars=True, on_new_output=None): """ Loads the requested variables from the matlab shell. names_to_get can be either a variable name, a list of variable names, or None. If it is a variable name, the values is returned. If it is a list, a dictionary of variable_name -> value is returned. If it is None, a dictionary with all variables is returned. If extract_numpy_scalars is true, the method will convert numpy scalars (0-dimension arrays) to a regular python variable. """ self._check_open() single_item = isinstance(names_to_get, (unicode, str)) if single_item: names_to_get = [names_to_get] if names_to_get == None: self.process.stdin.write('save stdio;\n') else: # Make sure that we throw an excpetion if the names are not defined. for name in names_to_get: self.eval('%s;' % name, print_expression=False, on_new_output=on_new_output) #print 'save(\'stdio\', \'%s\');\n' % '\', \''.join(names_to_get) self.process.stdin.write( "save('stdio', '%s', '-v7');\n" % '\', \''.join(names_to_get)) # We have to read to a temp buffer because mlabio.loadmat needs # random access :( self._read_until('start_binary\n', on_new_output=on_new_output) #print 'got start_binary' temp_str = self._sync_output(on_new_output=on_new_output) #print 'got all outout' # Remove expected output and "\n>>" # TODO(dani): Get rid of the unecessary copy. # MATLAB 2010a adds an extra >> so we need to remove more spaces. if self.matlab_version == (2010, 'a'): temp_str = temp_str[:-len(self.expected_output_end)-6] else: temp_str = temp_str[:-len(self.expected_output_end)-3] temp = StringIO(temp_str) #print ('____') #print len(temp_str) #print ('____') ret = mlabio.loadmat(temp, chars_as_strings=True, squeeze_me=True) #print '******' #print ret #print '******' temp.close() if single_item: return ret.values()[0] for key in ret.iterkeys(): while ret[key].shape and ret[key].shape[-1] == 1: ret[key] = ret[key][0] if extract_numpy_scalars: if isinstance(ret[key], np.ndarray) and not ret[key].shape: ret[key] = ret[key].tolist() #print 'done' return ret
Return the named groups in a regular expression (compiled or as string) in occuring order. >>> rexGroups(r'(?P<name>\w+) +(?P<surname>\w+)') ('name', 'surname') def rexGroups(rex): """Return the named groups in a regular expression (compiled or as string) in occuring order. >>> rexGroups(r'(?P<name>\w+) +(?P<surname>\w+)') ('name', 'surname') """ if isinstance(rex,basestring): rex = re.compile(rex) return zip(*sorted([(n,g) for (g,n) in rex.groupindex.items()]))[1]
``div(a,b)`` is like ``a // b`` if ``b`` devides ``a``, otherwise an `ValueError` is raised. >>> div(10,2) 5 >>> div(10,3) Traceback (most recent call last): ... ValueError: 3 does not divide 10 def div(a,b): """``div(a,b)`` is like ``a // b`` if ``b`` devides ``a``, otherwise an `ValueError` is raised. >>> div(10,2) 5 >>> div(10,3) Traceback (most recent call last): ... ValueError: 3 does not divide 10 """ res, fail = divmod(a,b) if fail: raise ValueError("%r does not divide %r" % (b,a)) else: return res
r"""Shuffle list `l` inplace and return it. def ipshuffle(l, random=None): r"""Shuffle list `l` inplace and return it.""" import random as _random _random.shuffle(l, random) return l
r"""Return shuffled *copy* of `seq`. def shuffle(seq, random=None): r"""Return shuffled *copy* of `seq`.""" if isinstance(seq, list): return ipshuffle(seq[:], random) elif isString(seq): # seq[0:0] == "" or u"" return seq[0:0].join(ipshuffle(list(seq)),random) else: return type(seq)(ipshuffle(list(seq),random))
r"""Read in a complete file `file` as a string Parameters: - `file`: a file handle or a string (`str` or `unicode`). - `binary`: whether to read in the file in binary mode (default: False). def slurp(file, binary=False, expand=False): r"""Read in a complete file `file` as a string Parameters: - `file`: a file handle or a string (`str` or `unicode`). - `binary`: whether to read in the file in binary mode (default: False). """ mode = "r" + ["b",""][not binary] file = _normalizeToFile(file, mode=mode, expand=expand) try: return file.read() finally: file.close()
Pass `file` to `func` and ensure the file is closed afterwards. If `file` is a string, open according to `mode`; if `expand` is true also expand user and vars. def withFile(file, func, mode='r', expand=False): """Pass `file` to `func` and ensure the file is closed afterwards. If `file` is a string, open according to `mode`; if `expand` is true also expand user and vars. """ file = _normalizeToFile(file, mode=mode, expand=expand) try: return func(file) finally: file.close()
r"""Read in a complete file (specified by a file handler or a filename string/unicode string) as list of lines def slurpLines(file, expand=False): r"""Read in a complete file (specified by a file handler or a filename string/unicode string) as list of lines""" file = _normalizeToFile(file, "r", expand) try: return file.readlines() finally: file.close()
r"""Return ``file`` a list of chomped lines. See `slurpLines`. def slurpChompedLines(file, expand=False): r"""Return ``file`` a list of chomped lines. See `slurpLines`.""" f=_normalizeToFile(file, "r", expand) try: return list(chompLines(f)) finally: f.close()
Create a new tempfile, write ``s`` to it and return the filename. `suffix`, `prefix` and `dir` are like in `tempfile.mkstemp`. def strToTempfile(s, suffix=None, prefix=None, dir=None, binary=False): """Create a new tempfile, write ``s`` to it and return the filename. `suffix`, `prefix` and `dir` are like in `tempfile.mkstemp`. """ fd, filename = tempfile.mkstemp(**dict((k,v) for (k,v) in [('suffix',suffix),('prefix',prefix),('dir', dir)] if v is not None)) spitOut(s, fd, binary) return filename
r"""Write string `s` into `file` (which can be a string (`str` or `unicode`) or a `file` instance). def spitOut(s, file, binary=False, expand=False): r"""Write string `s` into `file` (which can be a string (`str` or `unicode`) or a `file` instance).""" mode = "w" + ["b",""][not binary] file = _normalizeToFile(file, mode=mode, expand=expand) try: file.write(s) finally: file.close()
r"""Write all the `lines` to `file` (which can be a string/unicode or a file handler). def spitOutLines(lines, file, expand=False): r"""Write all the `lines` to `file` (which can be a string/unicode or a file handler).""" file = _normalizeToFile(file, mode="w", expand=expand) try: file.writelines(lines) finally: file.close()
r"""Similar to `os.popen3`, but returns 2 strings (stdin, stdout) and the exit code (unlike popen2, exit is 0 if no problems occured (for some bizarre reason popen2 returns None... <sigh>). FIXME: only works for UNIX; handling of signalled processes. def readProcess(cmd, *args): r"""Similar to `os.popen3`, but returns 2 strings (stdin, stdout) and the exit code (unlike popen2, exit is 0 if no problems occured (for some bizarre reason popen2 returns None... <sigh>). FIXME: only works for UNIX; handling of signalled processes. """ import popen2 BUFSIZE=1024 import select popen = popen2.Popen3((cmd,) + args, capturestderr=True) which = {id(popen.fromchild): [], id(popen.childerr): []} select = Result(select.select) read = Result(os.read) try: popen.tochild.close() # XXX make sure we're not waiting forever while select([popen.fromchild, popen.childerr], [], []): readSomething = False for f in select.result[0]: while read(f.fileno(), BUFSIZE): which[id(f)].append(read.result) readSomething = True if not readSomething: break out, err = ["".join(which[id(f)]) for f in [popen.fromchild, popen.childerr]] returncode = popen.wait() if os.WIFEXITED(returncode): exit = os.WEXITSTATUS(returncode) else: exit = returncode or 1 # HACK: ensure non-zero finally: try: popen.fromchild.close() finally: popen.childerr.close() return out or "", err or "", exit
Run `cmd` (which is searched for in the executable path) with `args` and return the exit status. In general (unless you know what you're doing) use:: runProcess('program', filename) rather than:: os.system('program %s' % filename) because the latter will not work as expected if `filename` contains spaces or shell-metacharacters. If you need more fine-grained control look at ``os.spawn*``. def runProcess(cmd, *args): """Run `cmd` (which is searched for in the executable path) with `args` and return the exit status. In general (unless you know what you're doing) use:: runProcess('program', filename) rather than:: os.system('program %s' % filename) because the latter will not work as expected if `filename` contains spaces or shell-metacharacters. If you need more fine-grained control look at ``os.spawn*``. """ from os import spawnvp, P_WAIT return spawnvp(P_WAIT, cmd, (cmd,) + args)
r"""Like the normal splitext (in posixpath), but doesn't treat dotfiles (e.g. .emacs) as extensions. Also uses os.sep instead of '/'. def splitext(p): r"""Like the normal splitext (in posixpath), but doesn't treat dotfiles (e.g. .emacs) as extensions. Also uses os.sep instead of '/'.""" root, ext = os.path.splitext(p) # check for dotfiles if (not root or root[-1] == os.sep): # XXX: use '/' or os.sep here??? return (root + ext, "") else: return root, ext
r"""Like a partitioning version of `filter`. Returns ``[itemsForWhichFuncReturnedFalse, itemsForWhichFuncReturnedTrue]``. Example: >>> bipart(bool, [1,None,2,3,0,[],[0]]) [[None, 0, []], [1, 2, 3, [0]]] def bipart(func, seq): r"""Like a partitioning version of `filter`. Returns ``[itemsForWhichFuncReturnedFalse, itemsForWhichFuncReturnedTrue]``. Example: >>> bipart(bool, [1,None,2,3,0,[],[0]]) [[None, 0, []], [1, 2, 3, [0]]] """ if func is None: func = bool res = [[],[]] for i in seq: res[not not func(i)].append(i) return res
r"""Return the position of `item` in ordered sequence `seq`, using comparison function `cmpfunc` (defaults to ``cmp``) and return the first found position of `item`, or -1 if `item` is not in `seq`. The returned position is NOT guaranteed to be the first occurence of `item` in `seq`. def binarySearchPos(seq, item, cmpfunc=cmp): r"""Return the position of `item` in ordered sequence `seq`, using comparison function `cmpfunc` (defaults to ``cmp``) and return the first found position of `item`, or -1 if `item` is not in `seq`. The returned position is NOT guaranteed to be the first occurence of `item` in `seq`.""" if not seq: return -1 left, right = 0, len(seq) - 1 if cmpfunc(seq[left], item) == 1 and \ cmpfunc(seq[right], item) == -1: return -1 while left <= right: halfPoint = (left + right) // 2 comp = cmpfunc(seq[halfPoint], item) if comp > 0: right = halfPoint - 1 elif comp < 0: left = halfPoint + 1 else: return halfPoint return -1
r""" Search an ordered sequence `seq` for `item`, using comparison function `cmpfunc` (defaults to ``cmp``) and return the first found instance of `item`, or `None` if item is not in `seq`. The returned item is NOT guaranteed to be the first occurrence of item in `seq`. def binarySearchItem(seq, item, cmpfunc=cmp): r""" Search an ordered sequence `seq` for `item`, using comparison function `cmpfunc` (defaults to ``cmp``) and return the first found instance of `item`, or `None` if item is not in `seq`. The returned item is NOT guaranteed to be the first occurrence of item in `seq`.""" pos = binarySearchPos(seq, item, cmpfunc) if pos == -1: raise KeyError("Item not in seq") else: return seq[pos]
r"""Rotates a list `l` `steps` to the left. Accepts `steps` > `len(l)` or < 0. >>> rotate([1,2,3]) [2, 3, 1] >>> rotate([1,2,3,4],-2) [3, 4, 1, 2] >>> rotate([1,2,3,4],-5) [4, 1, 2, 3] >>> rotate([1,2,3,4],1) [2, 3, 4, 1] >>> l = [1,2,3]; rotate(l) is not l True def rotate(l, steps=1): r"""Rotates a list `l` `steps` to the left. Accepts `steps` > `len(l)` or < 0. >>> rotate([1,2,3]) [2, 3, 1] >>> rotate([1,2,3,4],-2) [3, 4, 1, 2] >>> rotate([1,2,3,4],-5) [4, 1, 2, 3] >>> rotate([1,2,3,4],1) [2, 3, 4, 1] >>> l = [1,2,3]; rotate(l) is not l True """ if len(l): steps %= len(l) if steps: res = l[steps:] res.extend(l[:steps]) return res
r"""Like rotate, but modifies `l` in-place. >>> l = [1,2,3] >>> iprotate(l) is l True >>> l [2, 3, 1] >>> iprotate(iprotate(l, 2), -3) [1, 2, 3] def iprotate(l, steps=1): r"""Like rotate, but modifies `l` in-place. >>> l = [1,2,3] >>> iprotate(l) is l True >>> l [2, 3, 1] >>> iprotate(iprotate(l, 2), -3) [1, 2, 3] """ if len(l): steps %= len(l) if steps: firstPart = l[:steps] del l[:steps] l.extend(firstPart) return l
r"""Returns all unique items in `iterable` in the *same* order (only works if items in `seq` are hashable). def unique(iterable): r"""Returns all unique items in `iterable` in the *same* order (only works if items in `seq` are hashable). """ d = {} return (d.setdefault(x,x) for x in iterable if x not in d)
Returns the elements in `iterable` that aren't unique; stops after it found `reportMax` non-unique elements. Examples: >>> list(notUnique([1,1,2,2,3,3])) [1, 2, 3] >>> list(notUnique([1,1,2,2,3,3], 1)) [1] def notUnique(iterable, reportMax=INF): """Returns the elements in `iterable` that aren't unique; stops after it found `reportMax` non-unique elements. Examples: >>> list(notUnique([1,1,2,2,3,3])) [1, 2, 3] >>> list(notUnique([1,1,2,2,3,3], 1)) [1] """ hash = {} n=0 if reportMax < 1: raise ValueError("`reportMax` must be >= 1 and is %r" % reportMax) for item in iterable: count = hash[item] = hash.get(item, 0) + 1 if count > 1: yield item n += 1 if n >= reportMax: return
r"""Divide `iterable` in `n` lists, so that every `n`th element belongs to list `n`. Example: >>> unweave((1,2,3,4,5), 3) [[1, 4], [2, 5], [3]] def unweave(iterable, n=2): r"""Divide `iterable` in `n` lists, so that every `n`th element belongs to list `n`. Example: >>> unweave((1,2,3,4,5), 3) [[1, 4], [2, 5], [3]] """ res = [[] for i in range(n)] i = 0 for x in iterable: res[i % n].append(x) i += 1 return res
r"""weave(seq1 [, seq2] [...]) -> iter([seq1[0], seq2[0] ...]). >>> list(weave([1,2,3], [4,5,6,'A'], [6,7,8, 'B', 'C'])) [1, 4, 6, 2, 5, 7, 3, 6, 8] Any iterable will work. The first exhausted iterable determines when to stop. FIXME rethink stopping semantics. >>> list(weave(iter(('is','psu')), ('there','no', 'censorship'))) ['is', 'there', 'psu', 'no'] >>> list(weave(('there','no', 'censorship'), iter(('is','psu')))) ['there', 'is', 'no', 'psu', 'censorship'] def weave(*iterables): r"""weave(seq1 [, seq2] [...]) -> iter([seq1[0], seq2[0] ...]). >>> list(weave([1,2,3], [4,5,6,'A'], [6,7,8, 'B', 'C'])) [1, 4, 6, 2, 5, 7, 3, 6, 8] Any iterable will work. The first exhausted iterable determines when to stop. FIXME rethink stopping semantics. >>> list(weave(iter(('is','psu')), ('there','no', 'censorship'))) ['is', 'there', 'psu', 'no'] >>> list(weave(('there','no', 'censorship'), iter(('is','psu')))) ['there', 'is', 'no', 'psu', 'censorship'] """ iterables = map(iter, iterables) while True: for it in iterables: yield it.next()
r"""Return a list of items in `indexable` at positions `indices`. Examples: >>> atIndices([1,2,3], [1,1,0]) [2, 2, 1] >>> atIndices([1,2,3], [1,1,0,4], 'default') [2, 2, 1, 'default'] >>> atIndices({'a':3, 'b':0}, ['a']) [3] def atIndices(indexable, indices, default=__unique): r"""Return a list of items in `indexable` at positions `indices`. Examples: >>> atIndices([1,2,3], [1,1,0]) [2, 2, 1] >>> atIndices([1,2,3], [1,1,0,4], 'default') [2, 2, 1, 'default'] >>> atIndices({'a':3, 'b':0}, ['a']) [3] """ if default is __unique: return [indexable[i] for i in indices] else: res = [] for i in indices: try: res.append(indexable[i]) except (IndexError, KeyError): res.append(default) return res
r"""Move an `n`-item (default 2) windows `s` steps (default 1) at a time over `iterable`. Examples: >>> list(window(range(6),2)) [(0, 1), (1, 2), (2, 3), (3, 4), (4, 5)] >>> list(window(range(6),3)) [(0, 1, 2), (1, 2, 3), (2, 3, 4), (3, 4, 5)] >>> list(window(range(6),3, 2)) [(0, 1, 2), (2, 3, 4)] >>> list(window(range(5),3,2)) == list(window(range(6),3,2)) True def window(iterable, n=2, s=1): r"""Move an `n`-item (default 2) windows `s` steps (default 1) at a time over `iterable`. Examples: >>> list(window(range(6),2)) [(0, 1), (1, 2), (2, 3), (3, 4), (4, 5)] >>> list(window(range(6),3)) [(0, 1, 2), (1, 2, 3), (2, 3, 4), (3, 4, 5)] >>> list(window(range(6),3, 2)) [(0, 1, 2), (2, 3, 4)] >>> list(window(range(5),3,2)) == list(window(range(6),3,2)) True """ assert n >= s last = [] for elt in iterable: last.append(elt) if len(last) == n: yield tuple(last); last=last[s:]
r"""Iterate `n`-wise (default pairwise) over `iter`. Examples: >>> for (first, last) in group("Akira Kurosawa John Ford".split()): ... print "given name: %s surname: %s" % (first, last) ... given name: Akira surname: Kurosawa given name: John surname: Ford >>> >>> # both contain the same number of pairs >>> list(group(range(9))) == list(group(range(8))) True >>> # with n=3 >>> list(group(range(10), 3)) [(0, 1, 2), (3, 4, 5), (6, 7, 8)] >>> list(group(range(10), 3, pad=0)) [(0, 1, 2), (3, 4, 5), (6, 7, 8), (9, 0, 0)] def group(iterable, n=2, pad=__unique): r"""Iterate `n`-wise (default pairwise) over `iter`. Examples: >>> for (first, last) in group("Akira Kurosawa John Ford".split()): ... print "given name: %s surname: %s" % (first, last) ... given name: Akira surname: Kurosawa given name: John surname: Ford >>> >>> # both contain the same number of pairs >>> list(group(range(9))) == list(group(range(8))) True >>> # with n=3 >>> list(group(range(10), 3)) [(0, 1, 2), (3, 4, 5), (6, 7, 8)] >>> list(group(range(10), 3, pad=0)) [(0, 1, 2), (3, 4, 5), (6, 7, 8), (9, 0, 0)] """ assert n>0 # ensure it doesn't loop forever if pad is not __unique: it = chain(iterable, (pad,)*(n-1)) else: it = iter(iterable) perTuple = xrange(n) while True: yield tuple([it.next() for i in perTuple])
>>> list(iterate(lambda x:x//2)(128)) [128, 64, 32, 16, 8, 4, 2, 1, 0] >>> list(iterate(lambda x:x//2, n=2)(128)) [128, 64] def iterate(f, n=None, last=__unique): """ >>> list(iterate(lambda x:x//2)(128)) [128, 64, 32, 16, 8, 4, 2, 1, 0] >>> list(iterate(lambda x:x//2, n=2)(128)) [128, 64] """ if n is not None: def funciter(start): for i in xrange(n): yield start; start = f(start) else: def funciter(start): while True: yield start last = f(start) if last == start: return last, start = start, last return funciter
>>> list(dropwhilenot(lambda x:x==3, range(10))) [3, 4, 5, 6, 7, 8, 9] def dropwhilenot(func, iterable): """ >>> list(dropwhilenot(lambda x:x==3, range(10))) [3, 4, 5, 6, 7, 8, 9] """ iterable = iter(iterable) for x in iterable: if func(x): break else: return yield x for x in iterable: yield x
r"""Repeat each item in `iterable` `n` times. Example: >>> list(stretch(range(3), 2)) [0, 0, 1, 1, 2, 2] def stretch(iterable, n=2): r"""Repeat each item in `iterable` `n` times. Example: >>> list(stretch(range(3), 2)) [0, 0, 1, 1, 2, 2] """ times = range(n) for item in iterable: for i in times: yield item
r"""Yield chunks of `iterable`, split at the points in `indices`: >>> [l for l in splitAt(range(10), [2,5])] [[0, 1], [2, 3, 4], [5, 6, 7, 8, 9]] splits past the length of `iterable` are ignored: >>> [l for l in splitAt(range(10), [2,5,10])] [[0, 1], [2, 3, 4], [5, 6, 7, 8, 9]] def splitAt(iterable, indices): r"""Yield chunks of `iterable`, split at the points in `indices`: >>> [l for l in splitAt(range(10), [2,5])] [[0, 1], [2, 3, 4], [5, 6, 7, 8, 9]] splits past the length of `iterable` are ignored: >>> [l for l in splitAt(range(10), [2,5,10])] [[0, 1], [2, 3, 4], [5, 6, 7, 8, 9]] """ iterable = iter(iterable) now = 0 for to in indices: try: res = [] for i in range(now, to): res.append(iterable.next()) except StopIteration: yield res; return yield res now = to res = list(iterable) if res: yield res
Return a copy of dict `d` updated with dict `e`. def update(d, e): """Return a copy of dict `d` updated with dict `e`.""" res = copy.copy(d) res.update(e) return res
r"""Return an inverted version of dict `d`, so that values become keys and vice versa. If multiple keys in `d` have the same value an error is raised, unless `allowManyToOne` is true, in which case one of those key-value pairs is chosen at random for the inversion. Examples: >>> invertDict({1: 2, 3: 4}) == {2: 1, 4: 3} True >>> invertDict({1: 2, 3: 2}) Traceback (most recent call last): File "<stdin>", line 1, in ? ValueError: d can't be inverted! >>> invertDict({1: 2, 3: 2}, allowManyToOne=True).keys() [2] def invertDict(d, allowManyToOne=False): r"""Return an inverted version of dict `d`, so that values become keys and vice versa. If multiple keys in `d` have the same value an error is raised, unless `allowManyToOne` is true, in which case one of those key-value pairs is chosen at random for the inversion. Examples: >>> invertDict({1: 2, 3: 4}) == {2: 1, 4: 3} True >>> invertDict({1: 2, 3: 2}) Traceback (most recent call last): File "<stdin>", line 1, in ? ValueError: d can't be inverted! >>> invertDict({1: 2, 3: 2}, allowManyToOne=True).keys() [2] """ res = dict(izip(d.itervalues(), d.iterkeys())) if not allowManyToOne and len(res) != len(d): raise ValueError("d can't be inverted!") return res
r"""Like `flatten` but lazy. def iflatten(seq, isSeq=isSeq): r"""Like `flatten` but lazy.""" for elt in seq: if isSeq(elt): for x in iflatten(elt, isSeq): yield x else: yield elt
r"""Returns a flattened version of a sequence `seq` as a `list`. Parameters: - `seq`: The sequence to be flattened (any iterable). - `isSeq`: The function called to determine whether something is a sequence (default: `isSeq`). *Beware that this function should **never** test positive for strings, because they are no real sequences and thus cause infinite recursion.* Examples: >>> flatten([1,[2,3,(4,[5,6]),7,8]]) [1, 2, 3, 4, 5, 6, 7, 8] >>> # flaten only lists >>> flatten([1,[2,3,(4,[5,6]),7,8]], isSeq=lambda x:isinstance(x, list)) [1, 2, 3, (4, [5, 6]), 7, 8] >>> flatten([1,2]) [1, 2] >>> flatten([]) [] >>> flatten('123') ['1', '2', '3'] def flatten(seq, isSeq=isSeq): r"""Returns a flattened version of a sequence `seq` as a `list`. Parameters: - `seq`: The sequence to be flattened (any iterable). - `isSeq`: The function called to determine whether something is a sequence (default: `isSeq`). *Beware that this function should **never** test positive for strings, because they are no real sequences and thus cause infinite recursion.* Examples: >>> flatten([1,[2,3,(4,[5,6]),7,8]]) [1, 2, 3, 4, 5, 6, 7, 8] >>> # flaten only lists >>> flatten([1,[2,3,(4,[5,6]),7,8]], isSeq=lambda x:isinstance(x, list)) [1, 2, 3, (4, [5, 6]), 7, 8] >>> flatten([1,2]) [1, 2] >>> flatten([]) [] >>> flatten('123') ['1', '2', '3'] """ return [a for elt in seq for a in (isSeq(elt) and flatten(elt, isSeq) or [elt])]
>>> positionIf(lambda x: x > 3, range(10)) 4 def positionIf(pred, seq): """ >>> positionIf(lambda x: x > 3, range(10)) 4 """ for i,e in enumerate(seq): if pred(e): return i return -1
r"""Return the set union of `seq1` and `seqs`, duplicates removed, order random. Examples: >>> union() [] >>> union([1,2,3]) [1, 2, 3] >>> union([1,2,3], {1:2, 5:1}) [1, 2, 3, 5] >>> union((1,2,3), ['a'], "bcd") ['a', 1, 2, 3, 'd', 'b', 'c'] >>> union([1,2,3], iter([0,1,1,1])) [0, 1, 2, 3] def union(seq1=(), *seqs): r"""Return the set union of `seq1` and `seqs`, duplicates removed, order random. Examples: >>> union() [] >>> union([1,2,3]) [1, 2, 3] >>> union([1,2,3], {1:2, 5:1}) [1, 2, 3, 5] >>> union((1,2,3), ['a'], "bcd") ['a', 1, 2, 3, 'd', 'b', 'c'] >>> union([1,2,3], iter([0,1,1,1])) [0, 1, 2, 3] """ if not seqs: return list(seq1) res = set(seq1) for seq in seqs: res.update(set(seq)) return list(res)
r"""Return a list with all elements in `seq2` removed from `seq1`, order preserved. Examples: >>> without([1,2,3,1,2], [1]) [2, 3, 2] def without(seq1, seq2): r"""Return a list with all elements in `seq2` removed from `seq1`, order preserved. Examples: >>> without([1,2,3,1,2], [1]) [2, 3, 2] """ if isSet(seq2): d2 = seq2 else: d2 = set(seq2) return [elt for elt in seq1 if elt not in d2]
>>> some(lambda x: x, [0, False, None]) False >>> some(lambda x: x, [None, 0, 2, 3]) 2 >>> some(operator.eq, [0,1,2], [2,1,0]) True >>> some(operator.eq, [1,2], [2,1]) False def some(predicate, *seqs): """ >>> some(lambda x: x, [0, False, None]) False >>> some(lambda x: x, [None, 0, 2, 3]) 2 >>> some(operator.eq, [0,1,2], [2,1,0]) True >>> some(operator.eq, [1,2], [2,1]) False """ try: if len(seqs) == 1: return ifilter(bool,imap(predicate, seqs[0])).next() else: return ifilter(bool,starmap(predicate, izip(*seqs))).next() except StopIteration: return False
r"""Like `some`, but only returns `True` if all the elements of `iterables` satisfy `predicate`. Examples: >>> every(bool, []) True >>> every(bool, [0]) False >>> every(bool, [1,1]) True >>> every(operator.eq, [1,2,3],[1,2]) True >>> every(operator.eq, [1,2,3],[0,2]) False def every(predicate, *iterables): r"""Like `some`, but only returns `True` if all the elements of `iterables` satisfy `predicate`. Examples: >>> every(bool, []) True >>> every(bool, [0]) False >>> every(bool, [1,1]) True >>> every(operator.eq, [1,2,3],[1,2]) True >>> every(operator.eq, [1,2,3],[0,2]) False """ try: if len(iterables) == 1: ifilterfalse(predicate, iterables[0]).next() else: ifilterfalse(bool, starmap(predicate, izip(*iterables))).next() except StopIteration: return True else: return False
r"""Call `f` `n` times with `args` and `kwargs`. Useful e.g. for simplistic timing. Examples: >>> nTimes(3, sys.stdout.write, 'hallo\n') hallo hallo hallo def nTimes(n, f, *args, **kwargs): r"""Call `f` `n` times with `args` and `kwargs`. Useful e.g. for simplistic timing. Examples: >>> nTimes(3, sys.stdout.write, 'hallo\n') hallo hallo hallo """ for i in xrange(n): f(*args, **kwargs)
r"""Return the time (in ms) it takes to call a function (the first argument) with the remaining arguments and `kwargs`. Examples: To find out how long ``func('foo', spam=1)`` takes to execute, do: ``timeCall(func, foo, spam=1)`` def timeCall(*funcAndArgs, **kwargs): r"""Return the time (in ms) it takes to call a function (the first argument) with the remaining arguments and `kwargs`. Examples: To find out how long ``func('foo', spam=1)`` takes to execute, do: ``timeCall(func, foo, spam=1)`` """ func, args = funcAndArgs[0], funcAndArgs[1:] start = time.time() func(*args, **kwargs) return time.time() - start
r"""Replace all ``(frm, to)`` tuples in `args` in string `s`. >>> replaceStrs("nothing is better than warm beer", ... ('nothing','warm beer'), ('warm beer','nothing')) 'warm beer is better than nothing' def replaceStrs(s, *args): r"""Replace all ``(frm, to)`` tuples in `args` in string `s`. >>> replaceStrs("nothing is better than warm beer", ... ('nothing','warm beer'), ('warm beer','nothing')) 'warm beer is better than nothing' """ if args == (): return s mapping = dict((frm, to) for frm, to in args) return re.sub("|".join(map(re.escape, mapping.keys())), lambda match:mapping[match.group(0)], s)
r"""Inverse of `escape`. >>> unescape(r'\x41\n\x42\n\x43') 'A\nB\nC' >>> unescape(r'\u86c7') u'\u86c7' >>> unescape(u'ah') u'ah' def unescape(s): r"""Inverse of `escape`. >>> unescape(r'\x41\n\x42\n\x43') 'A\nB\nC' >>> unescape(r'\u86c7') u'\u86c7' >>> unescape(u'ah') u'ah' """ if re.search(r'(?<!\\)\\(\\\\)*[uU]', s) or isinstance(s, unicode): return unescapeUnicode(s) else: return unescapeAscii(s)
r"""Return line and column of `pos` (0-based!) in `s`. Lines start with 1, columns with 0. Examples: >>> lineAndColumnAt("0123\n56", 5) (2, 0) >>> lineAndColumnAt("0123\n56", 6) (2, 1) >>> lineAndColumnAt("0123\n56", 0) (1, 0) def lineAndColumnAt(s, pos): r"""Return line and column of `pos` (0-based!) in `s`. Lines start with 1, columns with 0. Examples: >>> lineAndColumnAt("0123\n56", 5) (2, 0) >>> lineAndColumnAt("0123\n56", 6) (2, 1) >>> lineAndColumnAt("0123\n56", 0) (1, 0) """ if pos >= len(s): raise IndexError("`pos` %d not in string" % pos) # *don't* count last '\n', if it is at pos! line = s.count('\n',0,pos) if line: return line + 1, pos - s.rfind('\n',0,pos) - 1 else: return 1, pos
r"""Like ``print``, but a function. I.e. prints out all arguments as ``print`` would do. Specify output stream like this:: print('ERROR', `out="sys.stderr"``). def prin(*args, **kwargs): r"""Like ``print``, but a function. I.e. prints out all arguments as ``print`` would do. Specify output stream like this:: print('ERROR', `out="sys.stderr"``). """ print >> kwargs.get('out',None), " ".join([str(arg) for arg in args])
r"""Truncate `s` if necessary to fit into a line of width `maxCol` (default: 79), also replacing newlines with `newlineReplacement` (default `None`: in which case everything after the first newline is simply discarded). Examples: >>> fitString('12345', maxCol=5) '12345' >>> fitString('123456', maxCol=5) '12...' >>> fitString('a line\na second line') 'a line' >>> fitString('a line\na second line', newlineReplacement='\\n') 'a line\\na second line' def fitString(s, maxCol=79, newlineReplacement=None): r"""Truncate `s` if necessary to fit into a line of width `maxCol` (default: 79), also replacing newlines with `newlineReplacement` (default `None`: in which case everything after the first newline is simply discarded). Examples: >>> fitString('12345', maxCol=5) '12345' >>> fitString('123456', maxCol=5) '12...' >>> fitString('a line\na second line') 'a line' >>> fitString('a line\na second line', newlineReplacement='\\n') 'a line\\na second line' """ assert isString(s) if '\n' in s: if newlineReplacement is None: s = s[:s.index('\n')] else: s = s.replace("\n", newlineReplacement) if maxCol is not None and len(s) > maxCol: s = "%s..." % s[:maxCol-3] return s
r"""Pickle name and value of all those variables in `outOf` (default: all global variables (as seen from the caller)) that are named in `varNamesStr` into a file called `filename` (if no extension is given, '.bpickle' is appended). Overwrites file without asking, unless you specify `overwrite=0`. Load again with `loadVars`. Thus, to save the global variables ``bar``, ``foo`` and ``baz`` in the file 'savedVars' do:: saveVars('savedVars', 'bar foo baz') def saveVars(filename, varNamesStr, outOf=None, **opts): r"""Pickle name and value of all those variables in `outOf` (default: all global variables (as seen from the caller)) that are named in `varNamesStr` into a file called `filename` (if no extension is given, '.bpickle' is appended). Overwrites file without asking, unless you specify `overwrite=0`. Load again with `loadVars`. Thus, to save the global variables ``bar``, ``foo`` and ``baz`` in the file 'savedVars' do:: saveVars('savedVars', 'bar foo baz') """ filename, varnames, outOf = __saveVarsHelper( filename, varNamesStr, outOf, **opts) print "pickling:\n", "\n".join(sorted(varnames)) try: f = None f = open(filename, "wb") cPickle.dump(dict(zip(varnames, atIndices(outOf, varnames))), f, 1) # UGH: cPickle, unlike pickle doesn't accept bin=1 finally: if f: f.close()
r"""Like `saveVars`, but appends additional variables to file. def addVars(filename, varNamesStr, outOf=None): r"""Like `saveVars`, but appends additional variables to file.""" filename, varnames, outOf = __saveVarsHelper(filename, varNamesStr, outOf) f = None try: f = open(filename, "rb") h = cPickle.load(f) f.close() h.update(dict(zip(varnames, atIndices(outOf, varnames)))) f = open(filename, "wb") cPickle.dump( h, f , 1 ) finally: if f: f.close()
Return the variables pickled pickled into `filename` with `saveVars` as a dict. def loadDict(filename): """Return the variables pickled pickled into `filename` with `saveVars` as a dict.""" filename = os.path.expanduser(filename) if not splitext(filename)[1]: filename += ".bpickle" f = None try: f = open(filename, "rb") varH = cPickle.load(f) finally: if f: f.close() return varH
r"""Load variables pickled with `saveVars`. Parameters: - `ask`: If `True` then don't overwrite existing variables without asking. - `only`: A list to limit the variables to or `None`. - `into`: The dictionary the variables should be loaded into (defaults to global dictionary). def loadVars(filename, ask=True, into=None, only=None): r"""Load variables pickled with `saveVars`. Parameters: - `ask`: If `True` then don't overwrite existing variables without asking. - `only`: A list to limit the variables to or `None`. - `into`: The dictionary the variables should be loaded into (defaults to global dictionary). """ filename = os.path.expanduser(filename) if into is None: into = magicGlobals() varH = loadDict(filename) toUnpickle = only or varH.keys() alreadyDefined = filter(into.has_key, toUnpickle) if alreadyDefined and ask: print "The following vars already exist; overwrite (yes/NO)?\n",\ "\n".join(alreadyDefined) if raw_input() != "yes": toUnpickle = without(toUnpickle, alreadyDefined) if not toUnpickle: print "nothing to unpickle" return None print "unpickling:\n",\ "\n".join(sorted(toUnpickle)) for k in varH.keys(): if k not in toUnpickle: del varH[k] into.update(varH)
r"""Create a short info string detailing how a program was invoked. This is meant to be added to a history comment field of a data file were it is important to keep track of what programs modified it and how. !!!:`args` should be a **``list``** not a ``str``. def runInfo(prog=None,vers=None,date=None,user=None,dir=None,args=None): r"""Create a short info string detailing how a program was invoked. This is meant to be added to a history comment field of a data file were it is important to keep track of what programs modified it and how. !!!:`args` should be a **``list``** not a ``str``.""" return "%(prog)s %(vers)s;" \ " run %(date)s by %(usr)s in %(dir)s with: %(args)s'n" % \ mkDict(prog=prog or sys.argv[0], vers=vers or magicGlobals().get("__version__", ""), date=date or isoDateTimeStr(), usr=user or getpass.getuser(), dir=dir or os.getcwd(), args=" ".join(args or sys.argv))
r"""Creates functions that print out their argument, (between optional `pre` and `post` strings) and return it unmodified. This is usefull for debugging e.g. parts of expressions, without having to modify the behavior of the program. Example: >>> makePrintReturner(pre="The value is:", post="[returning]")(3) The value is: 3 [returning] 3 >>> def makePrintReturner(pre="", post="" ,out=None): r"""Creates functions that print out their argument, (between optional `pre` and `post` strings) and return it unmodified. This is usefull for debugging e.g. parts of expressions, without having to modify the behavior of the program. Example: >>> makePrintReturner(pre="The value is:", post="[returning]")(3) The value is: 3 [returning] 3 >>> """ def printReturner(arg): myArgs = [pre, arg, post] prin(*myArgs, **{'out':out}) return arg return printReturner
Returns a 'verbose' version of container instance `cont`, that will execute `onGet`, `onSet` and `onDel` (if not `None`) every time __getitem__, __setitem__ and __delitem__ are called, passing `self`, `key` (and `value` in the case of set). E.g: >>> l = [1,2,3] >>> l = asVerboseContainer(l, ... onGet=lambda s,k:k==2 and prin('Got two:', k), ... onSet=lambda s,k,v:k == v and prin('k == v:', k, v), ... onDel=lambda s,k:k == 1 and prin('Deleting one:', k)) >>> l [1, 2, 3] >>> l[1] 2 >>> l[2] Got two: 2 3 >>> l[2] = 22 >>> l[2] = 2 k == v: 2 2 >>> del l[2] >>> del l[1] Deleting one: 1 def asVerboseContainer(cont, onGet=None, onSet=None, onDel=None): """Returns a 'verbose' version of container instance `cont`, that will execute `onGet`, `onSet` and `onDel` (if not `None`) every time __getitem__, __setitem__ and __delitem__ are called, passing `self`, `key` (and `value` in the case of set). E.g: >>> l = [1,2,3] >>> l = asVerboseContainer(l, ... onGet=lambda s,k:k==2 and prin('Got two:', k), ... onSet=lambda s,k,v:k == v and prin('k == v:', k, v), ... onDel=lambda s,k:k == 1 and prin('Deleting one:', k)) >>> l [1, 2, 3] >>> l[1] 2 >>> l[2] Got two: 2 3 >>> l[2] = 22 >>> l[2] = 2 k == v: 2 2 >>> del l[2] >>> del l[1] Deleting one: 1 """ class VerboseContainer(type(cont)): if onGet: def __getitem__(self, key): onGet(self, key) return super(VerboseContainer, self).__getitem__(key) if onSet: def __setitem__(self, key, value): onSet(self, key, value) return super(VerboseContainer, self).__setitem__(key, value) if onDel: def __delitem__(self, key): onDel(self, key) return super(VerboseContainer, self).__delitem__(key) return VerboseContainer(cont)
r"""Convinience function to implement ``__repr__``. `kwargs` values are ``repr`` ed. Special behavior for ``instance=None``: just the arguments are formatted. Example: >>> class Thing: ... def __init__(self, color, shape, taste=None): ... self.color, self.shape, self.taste = color, shape, taste ... def __repr__(self): ... return mkRepr(self, self.color, self.shape, taste=self.taste) ... >>> maggot = Thing('white', 'cylindrical', 'chicken') >>> maggot Thing('white', 'cylindrical', taste='chicken') >>> Thing('Color # 132942430-214809804-412430988081-241234', 'unkown', taste=maggot) Thing('Color # 132942430-214809804-412430988081-241234', 'unkown', taste=Thing('white', 'cylindrical', taste='chicken')) def mkRepr(instance, *argls, **kwargs): r"""Convinience function to implement ``__repr__``. `kwargs` values are ``repr`` ed. Special behavior for ``instance=None``: just the arguments are formatted. Example: >>> class Thing: ... def __init__(self, color, shape, taste=None): ... self.color, self.shape, self.taste = color, shape, taste ... def __repr__(self): ... return mkRepr(self, self.color, self.shape, taste=self.taste) ... >>> maggot = Thing('white', 'cylindrical', 'chicken') >>> maggot Thing('white', 'cylindrical', taste='chicken') >>> Thing('Color # 132942430-214809804-412430988081-241234', 'unkown', taste=maggot) Thing('Color # 132942430-214809804-412430988081-241234', 'unkown', taste=Thing('white', 'cylindrical', taste='chicken')) """ width=79 maxIndent=15 minIndent=2 args = (map(repr, argls) + ["%s=%r" % (k, v) for (k,v) in sorted(kwargs.items())]) or [""] if instance is not None: start = "%s(" % instance.__class__.__name__ args[-1] += ")" else: start = "" if len(start) <= maxIndent and len(start) + len(args[0]) <= width and \ max(map(len,args)) <= width: # XXX mag of last condition bit arbitrary indent = len(start) args[0] = start + args[0] if sum(map(len, args)) + 2*(len(args) - 1) <= width: return ", ".join(args) else: indent = minIndent args[0] = start + "\n" + " " * indent + args[0] return (",\n" + " " * indent).join(args)
Utility function to remove ``**kwargs`` parsing boiler-plate in ``__init__``: >>> kwargs = dict(name='Bill', age=51, income=1e7) >>> self = ezstruct(); d2attrs(kwargs, self, 'income', 'name'); self ezstruct(income=10000000.0, name='Bill') >>> self = ezstruct(); d2attrs(kwargs, self, 'income', age=0, bloodType='A'); self ezstruct(age=51, bloodType='A', income=10000000.0) To set all keys from ``kwargs`` use: >>> self = ezstruct(); d2attrs(kwargs, self, 'all!'); self ezstruct(age=51, income=10000000.0, name='Bill') def d2attrs(*args, **kwargs): """Utility function to remove ``**kwargs`` parsing boiler-plate in ``__init__``: >>> kwargs = dict(name='Bill', age=51, income=1e7) >>> self = ezstruct(); d2attrs(kwargs, self, 'income', 'name'); self ezstruct(income=10000000.0, name='Bill') >>> self = ezstruct(); d2attrs(kwargs, self, 'income', age=0, bloodType='A'); self ezstruct(age=51, bloodType='A', income=10000000.0) To set all keys from ``kwargs`` use: >>> self = ezstruct(); d2attrs(kwargs, self, 'all!'); self ezstruct(age=51, income=10000000.0, name='Bill') """ (d, self), args = args[:2], args[2:] if args[0] == 'all!': assert len(args) == 1 for k in d: setattr(self, k, d[k]) else: if len(args) != len(set(args)) or set(kwargs) & set(args): raise ValueError('Duplicate keys: %s' % list(notUnique(args)) + list(set(kwargs) & set(args))) for k in args: if k in kwargs: raise ValueError('%s specified twice' % k) setattr(self, k, d[k]) for dk in kwargs: setattr(self, dk, d.get(dk, kwargs[dk]))
>>> pairwise(operator.sub, [4,3,2,1,-10]) [1, 1, 1, 11] >>> import numpy >>> pairwise(numpy.subtract, numpy.array([4,3,2,1,-10])) array([ 1, 1, 1, 11]) def pairwise(fun, v): """ >>> pairwise(operator.sub, [4,3,2,1,-10]) [1, 1, 1, 11] >>> import numpy >>> pairwise(numpy.subtract, numpy.array([4,3,2,1,-10])) array([ 1, 1, 1, 11]) """ if not hasattr(v, 'shape'): return list(ipairwise(fun,v)) else: return fun(v[:-1],v[1:])
>>> argmax([4,2,-5]) 0 >>> argmax([4,2,-5], key=abs) 2 >>> argmax([4,2,-5], key=abs, both=True) (2, 5) def argmax(iterable, key=None, both=False): """ >>> argmax([4,2,-5]) 0 >>> argmax([4,2,-5], key=abs) 2 >>> argmax([4,2,-5], key=abs, both=True) (2, 5) """ if key is not None: it = imap(key, iterable) else: it = iter(iterable) score, argmax = reduce(max, izip(it, count())) if both: return argmax, score return argmax
See `argmax`. def argmin(iterable, key=None, both=False): """See `argmax`. """ if key is not None: it = imap(key, iterable) else: it = iter(iterable) score, argmin = reduce(min, izip(it, count())) if both: return argmin, score return argmin
Returns true if `num` is (sort of) an integer. >>> isInt(3) == isInt(3.0) == 1 True >>> isInt(3.2) False >>> import numpy >>> isInt(numpy.array(1)) True >>> isInt(numpy.array([1])) False def isInt(num): """Returns true if `num` is (sort of) an integer. >>> isInt(3) == isInt(3.0) == 1 True >>> isInt(3.2) False >>> import numpy >>> isInt(numpy.array(1)) True >>> isInt(numpy.array([1])) False """ try: len(num) # FIXME fails for Numeric but Numeric is obsolete except: try: return (num - math.floor(num) == 0) == True except: return False else: return False
Similar to `map` but the instead of collecting the return values of `func` in a list, the items of each return value are instaed collected (so `func` must return an iterable type). Examples: >>> mapConcat(lambda x:[x], [1,2,3]) [1, 2, 3] >>> mapConcat(lambda x: [x,str(x)], [1,2,3]) [1, '1', 2, '2', 3, '3'] def mapConcat(func, *iterables): """Similar to `map` but the instead of collecting the return values of `func` in a list, the items of each return value are instaed collected (so `func` must return an iterable type). Examples: >>> mapConcat(lambda x:[x], [1,2,3]) [1, 2, 3] >>> mapConcat(lambda x: [x,str(x)], [1,2,3]) [1, '1', 2, '2', 3, '3'] """ return [e for l in imap(func, *iterables) for e in l]
>>> list(unfold(1234, lambda x: divmod(x,10)))[::-1] [1, 2, 3, 4] >>> sum(imap(operator.mul,unfold(1234, lambda x:divmod(x,10)), iterate(lambda x:x*10)(1))) 1234 >>> g = unfold(1234, lambda x:divmod(x,10)) >>> reduce((lambda (total,pow),digit:(total+pow*digit, 10*pow)), g, (0,1)) (1234, 10000) def unfold(seed, by, last = __unique): """ >>> list(unfold(1234, lambda x: divmod(x,10)))[::-1] [1, 2, 3, 4] >>> sum(imap(operator.mul,unfold(1234, lambda x:divmod(x,10)), iterate(lambda x:x*10)(1))) 1234 >>> g = unfold(1234, lambda x:divmod(x,10)) >>> reduce((lambda (total,pow),digit:(total+pow*digit, 10*pow)), g, (0,1)) (1234, 10000) """ while True: seed, val = by(seed); if last == seed: return last = seed; yield val
*R*ight reduce. >>> reduceR(lambda x,y:x/y, [1.,2.,3.,4]) == 1./(2./(3./4.)) == (1./2.)*(3./4.) True >>> reduceR(lambda x,y:x-y, iter([1,2,3]),4) == 1-(2-(3-4)) == (1-2)+(3-4) True def reduceR(f, sequence, initial=__unique): """*R*ight reduce. >>> reduceR(lambda x,y:x/y, [1.,2.,3.,4]) == 1./(2./(3./4.)) == (1./2.)*(3./4.) True >>> reduceR(lambda x,y:x-y, iter([1,2,3]),4) == 1-(2-(3-4)) == (1-2)+(3-4) True """ try: rev = reversed(sequence) except TypeError: rev = reversed(list(sequence)) if initial is __unique: return reduce(lambda x,y:f(y,x), rev) else: return reduce(lambda x,y:f(y,x), rev, initial)
Compose `funcs` to a single function. >>> compose(operator.abs, operator.add)(-2,-3) 5 >>> compose()('nada') 'nada' >>> compose(sorted, set, partial(filter, None))(range(3)[::-1]*2) [1, 2] def compose(*funcs): """Compose `funcs` to a single function. >>> compose(operator.abs, operator.add)(-2,-3) 5 >>> compose()('nada') 'nada' >>> compose(sorted, set, partial(filter, None))(range(3)[::-1]*2) [1, 2] """ # slightly optimized for most common cases and hence verbose if len(funcs) == 2: f0,f1=funcs; return lambda *a,**kw: f0(f1(*a,**kw)) elif len(funcs) == 3: f0,f1,f2=funcs; return lambda *a,**kw: f0(f1(f2(*a,**kw))) elif len(funcs) == 0: return lambda x:x # XXX single kwarg elif len(funcs) == 1: return funcs[0] else: def composed(*args,**kwargs): y = funcs[-1](*args,**kwargs) for f in funcs[:0:-1]: y = f(y) return y return composed
>>> romanNumeral(13) 'XIII' >>> romanNumeral(2944) 'MMCMXLIV' def romanNumeral(n): """ >>> romanNumeral(13) 'XIII' >>> romanNumeral(2944) 'MMCMXLIV' """ if 0 > n > 4000: raise ValueError('``n`` must lie between 1 and 3999: %d' % n) roman = 'I IV V IX X XL L XC C CD D CM M'.split() arabic = [1, 4, 5, 9, 10, 40, 50, 90, 100, 400, 500, 900, 1000] res = [] while n>0: pos = bisect.bisect_right(arabic, n)-1 fit = n//arabic[pos] res.append(roman[pos]*fit); n -= fit * arabic[pos] return "".join(res)
>>> first(3,iter([1,2,3,4])) [1, 2, 3] >>> first(3,iter([1,2,3,4]), iter) #doctest: +ELLIPSIS <itertools.islice object at ...> >>> first(3,iter([1,2,3,4]), tuple) (1, 2, 3) def first(n, it, constructor=list): """ >>> first(3,iter([1,2,3,4])) [1, 2, 3] >>> first(3,iter([1,2,3,4]), iter) #doctest: +ELLIPSIS <itertools.islice object at ...> >>> first(3,iter([1,2,3,4]), tuple) (1, 2, 3) """ return constructor(itertools.islice(it,n))
>>> first(10,drop(10,xrange(sys.maxint),iter)) [10, 11, 12, 13, 14, 15, 16, 17, 18, 19] def drop(n, it, constructor=list): """ >>> first(10,drop(10,xrange(sys.maxint),iter)) [10, 11, 12, 13, 14, 15, 16, 17, 18, 19] """ return constructor(itertools.islice(it,n,None))
Same as ``self.dryRun`` if ``self.dry``, else same as ``self.wetRun``. def run(self, func, *args, **kwargs): """Same as ``self.dryRun`` if ``self.dry``, else same as ``self.wetRun``.""" if self.dry: return self.dryRun(func, *args, **kwargs) else: return self.wetRun(func, *args, **kwargs)
Instead of running function with `*args` and `**kwargs`, just print out the function call. def dryRun(self, func, *args, **kwargs): """Instead of running function with `*args` and `**kwargs`, just print out the function call.""" print >> self.out, \ self.formatterDict.get(func, self.defaultFormatter)(func, *args, **kwargs)
Iterate over all the bridges in the system. def iterbridges(): ''' Iterate over all the bridges in the system. ''' net_files = os.listdir(SYSFS_NET_PATH) for d in net_files: path = os.path.join(SYSFS_NET_PATH, d) if not os.path.isdir(path): continue if os.path.exists(os.path.join(path, b"bridge")): yield Bridge(d)
Create new bridge with the given name def addbr(name): ''' Create new bridge with the given name ''' fcntl.ioctl(ifconfig.sockfd, SIOCBRADDBR, name) return Bridge(name)
Iterate over all the interfaces in this bridge. def iterifs(self): ''' Iterate over all the interfaces in this bridge. ''' if_path = os.path.join(SYSFS_NET_PATH, self.name, b"brif") net_files = os.listdir(if_path) for iface in net_files: yield iface
Add the interface with the given name to this bridge. Equivalent to brctl addif [bridge] [interface]. def addif(self, iface): ''' Add the interface with the given name to this bridge. Equivalent to brctl addif [bridge] [interface]. ''' if type(iface) == ifconfig.Interface: devindex = iface.index else: devindex = ifconfig.Interface(iface).index ifreq = struct.pack('16si', self.name, devindex) fcntl.ioctl(ifconfig.sockfd, SIOCBRADDIF, ifreq) return self
Remove the interface with the given name from this bridge. Equivalent to brctl delif [bridge] [interface] def delif(self, iface): ''' Remove the interface with the given name from this bridge. Equivalent to brctl delif [bridge] [interface]''' if type(iface) == ifconfig.Interface: devindex = iface.index else: devindex = ifconfig.Interface(iface).index ifreq = struct.pack('16si', self.name, devindex) fcntl.ioctl(ifconfig.sockfd, SIOCBRDELIF, ifreq) return self
Brings down the bridge interface, and removes it. Equivalent to ifconfig [bridge] down && brctl delbr [bridge]. def delete(self): ''' Brings down the bridge interface, and removes it. Equivalent to ifconfig [bridge] down && brctl delbr [bridge]. ''' self.down() fcntl.ioctl(ifconfig.sockfd, SIOCBRDELBR, self.name) return self
Get a random (i.e., unique) string identifier def _get_random_id(): """ Get a random (i.e., unique) string identifier""" symbols = string.ascii_uppercase + string.ascii_lowercase + string.digits return ''.join(random.choice(symbols) for _ in range(15))
Get a filename of a built-in library file. def get_lib_filename(category, name): """ Get a filename of a built-in library file. """ base_dir = os.path.dirname(os.path.abspath(__file__)) if category == 'js': filename = os.path.join('js', '{0}.js'.format(name)) elif category == 'css': filename = os.path.join('css', '{0}.css'.format(name)) elif category == 'html': filename = os.path.join('html', '{0}.html'.format(name)) else: raise ValueError("Unknown category") return os.path.join(base_dir, 'lib', filename)
Import required Javascript libraries to Jupyter Notebook. def output_notebook( d3js_url="//d3js.org/d3.v3.min", requirejs_url="//cdnjs.cloudflare.com/ajax/libs/require.js/2.1.10/require.min.js", html_template=None ): """ Import required Javascript libraries to Jupyter Notebook. """ if html_template is None: html_template = read_lib('html', 'setup') setup_html = populate_template( html_template, d3js=d3js_url, requirejs=requirejs_url ) display_html(setup_html) return
Create HTML code block given the graph Javascript and CSS. def create_graph_html(js_template, css_template, html_template=None): """ Create HTML code block given the graph Javascript and CSS. """ if html_template is None: html_template = read_lib('html', 'graph') # Create div ID for the graph and give it to the JS and CSS templates so # they can reference the graph. graph_id = 'graph-{0}'.format(_get_random_id()) js = populate_template(js_template, graph_id=graph_id) css = populate_template(css_template, graph_id=graph_id) return populate_template( html_template, graph_id=graph_id, css=css, js=js )
Return newest compatible version. >>> version = get_newest_possible_languagetool_version() >>> version in [JAVA_6_COMPATIBLE_VERSION, LATEST_VERSION] True def get_newest_possible_languagetool_version(): """Return newest compatible version. >>> version = get_newest_possible_languagetool_version() >>> version in [JAVA_6_COMPATIBLE_VERSION, LATEST_VERSION] True """ java_path = find_executable('java') if not java_path: # Just ignore this and assume an old version of Java. It might not be # found because of a PATHEXT-related issue # (https://bugs.python.org/issue2200). return JAVA_6_COMPATIBLE_VERSION output = subprocess.check_output([java_path, '-version'], stderr=subprocess.STDOUT, universal_newlines=True) # https://www.oracle.com/technetwork/java/javase/versioning-naming-139433.html match = re.search( r'^java version "(?P<major1>\d+)\.(?P<major2>\d+)\.[^"]+"$', output, re.MULTILINE) if not match: raise SystemExit( 'Could not parse Java version from """{}""".'.format(output)) java_version = (int(match.group('major1')), int(match.group('major2'))) if java_version >= (1, 7): return LATEST_VERSION elif java_version >= (1, 6): warn('grammar-check would be able to use a newer version of ' 'LanguageTool if you had Java 7 or newer installed') return JAVA_6_COMPATIBLE_VERSION else: raise SystemExit( 'You need at least Java 6 to use grammar-check')
Iterate over all the interfaces in the system. If physical is true, then return only real physical interfaces (not 'lo', etc). def iterifs(physical=True): ''' Iterate over all the interfaces in the system. If physical is true, then return only real physical interfaces (not 'lo', etc).''' net_files = os.listdir(SYSFS_NET_PATH) interfaces = set() virtual = set() for d in net_files: path = os.path.join(SYSFS_NET_PATH, d) if not os.path.isdir(path): continue if not os.path.exists(os.path.join(path, b"device")): virtual.add(d) interfaces.add(d) # Some virtual interfaces don't show up in the above search, for example, # subinterfaces (e.g. eth0:1). To find those, we have to do an ioctl if not physical: # ifconfig gets a max of 30 interfaces. Good enough for us too. ifreqs = array.array("B", b"\x00" * SIZE_OF_IFREQ * 30) buf_addr, _buf_len = ifreqs.buffer_info() ifconf = struct.pack("iP", SIZE_OF_IFREQ * 30, buf_addr) ifconf_res = fcntl.ioctl(sockfd, SIOCGIFCONF, ifconf) ifreqs_len, _ = struct.unpack("iP", ifconf_res) assert ifreqs_len % SIZE_OF_IFREQ == 0, ( "Unexpected amount of data returned from ioctl. " "You're probably running on an unexpected architecture") res = ifreqs.tostring() for i in range(0, ifreqs_len, SIZE_OF_IFREQ): d = res[i:i+16].strip(b'\0') interfaces.add(d) results = interfaces - virtual if physical else interfaces for d in results: yield Interface(d)
Initialize the library def init(): ''' Initialize the library ''' globals()["sock"] = socket.socket(socket.AF_INET, socket.SOCK_STREAM) globals()["sockfd"] = globals()["sock"].fileno()
Bring up the bridge interface. Equivalent to ifconfig [iface] up. def up(self): ''' Bring up the bridge interface. Equivalent to ifconfig [iface] up. ''' # Get existing device flags ifreq = struct.pack('16sh', self.name, 0) flags = struct.unpack('16sh', fcntl.ioctl(sockfd, SIOCGIFFLAGS, ifreq))[1] # Set new flags flags = flags | IFF_UP ifreq = struct.pack('16sh', self.name, flags) fcntl.ioctl(sockfd, SIOCSIFFLAGS, ifreq)
Return True if the interface is up, False otherwise. def is_up(self): ''' Return True if the interface is up, False otherwise. ''' # Get existing device flags ifreq = struct.pack('16sh', self.name, 0) flags = struct.unpack('16sh', fcntl.ioctl(sockfd, SIOCGIFFLAGS, ifreq))[1] # Set new flags if flags & IFF_UP: return True else: return False
Obtain the device's mac address. def get_mac(self): ''' Obtain the device's mac address. ''' ifreq = struct.pack('16sH14s', self.name, AF_UNIX, b'\x00'*14) res = fcntl.ioctl(sockfd, SIOCGIFHWADDR, ifreq) address = struct.unpack('16sH14s', res)[2] mac = struct.unpack('6B8x', address) return ":".join(['%02X' % i for i in mac])
Set the device's mac address. Device must be down for this to succeed. def set_mac(self, newmac): ''' Set the device's mac address. Device must be down for this to succeed. ''' macbytes = [int(i, 16) for i in newmac.split(':')] ifreq = struct.pack('16sH6B8x', self.name, AF_UNIX, *macbytes) fcntl.ioctl(sockfd, SIOCSIFHWADDR, ifreq)