INSTRUCTION
stringlengths
1
46.3k
RESPONSE
stringlengths
75
80.2k
:type head: RandomListNode :rtype: RandomListNode
def copy_random_pointer_v1(head): """ :type head: RandomListNode :rtype: RandomListNode """ dic = dict() m = n = head while m: dic[m] = RandomListNode(m.label) m = m.next while n: dic[n].next = dic.get(n.next) dic[n].random = dic.get(n.random) n = ...
:type head: RandomListNode :rtype: RandomListNode
def copy_random_pointer_v2(head): """ :type head: RandomListNode :rtype: RandomListNode """ copy = defaultdict(lambda: RandomListNode(0)) copy[None] = None node = head while node: copy[node].label = node.label copy[node].next = copy[node.next] copy[node].random = ...
[summary] Arguments: n {[int]} -- [to analysed number] Returns: [list of lists] -- [all factors of the number n]
def get_factors(n): """[summary] Arguments: n {[int]} -- [to analysed number] Returns: [list of lists] -- [all factors of the number n] """ def factor(n, i, combi, res): """[summary] helper function Arguments: n {[int]} -- [number] ...
[summary] Computes all factors of n. Translated the function get_factors(...) in a call-stack modell. Arguments: n {[int]} -- [to analysed number] Returns: [list of lists] -- [all factors]
def get_factors_iterative1(n): """[summary] Computes all factors of n. Translated the function get_factors(...) in a call-stack modell. Arguments: n {[int]} -- [to analysed number] Returns: [list of lists] -- [all factors] """ todo, res = [(n, 2, [])], [] while...
[summary] analog as above Arguments: n {[int]} -- [description] Returns: [list of lists] -- [all factors of n]
def get_factors_iterative2(n): """[summary] analog as above Arguments: n {[int]} -- [description] Returns: [list of lists] -- [all factors of n] """ ans, stack, x = [], [], 2 while True: if x > n // x: if not stack: return ans ...
Dynamic Programming Algorithm for counting the length of longest increasing subsequence type sequence: List[int]
def longest_increasing_subsequence(sequence): """ Dynamic Programming Algorithm for counting the length of longest increasing subsequence type sequence: List[int] """ length = len(sequence) counts = [1 for _ in range(length)] for i in range(1, length): for j in range(0, i): ...
:type nums: List[int] :rtype: List[int]
def single_number3(nums): """ :type nums: List[int] :rtype: List[int] """ # isolate a^b from pairs using XOR ab = 0 for n in nums: ab ^= n # isolate right most bit from a^b right_most = ab & (-ab) # isolate a and b from a^b a, b = 0, 0 for n in nums: if ...
[summary] HELPER-FUNCTION calculates the (eulidean) distance between vector x and y. Arguments: x {[tuple]} -- [vector] y {[tuple]} -- [vector]
def distance(x,y): """[summary] HELPER-FUNCTION calculates the (eulidean) distance between vector x and y. Arguments: x {[tuple]} -- [vector] y {[tuple]} -- [vector] """ assert len(x) == len(y), "The vector must have same length" result = () sum = 0 for i in range(le...
[summary] Implements the nearest neighbor algorithm Arguments: x {[tupel]} -- [vector] tSet {[dict]} -- [training set] Returns: [type] -- [result of the AND-function]
def nearest_neighbor(x, tSet): """[summary] Implements the nearest neighbor algorithm Arguments: x {[tupel]} -- [vector] tSet {[dict]} -- [training set] Returns: [type] -- [result of the AND-function] """ assert isinstance(x, tuple) and isinstance(tSet, dict) curren...
:type num: str :rtype: bool
def is_strobogrammatic(num): """ :type num: str :rtype: bool """ comb = "00 11 88 69 96" i = 0 j = len(num) - 1 while i <= j: x = comb.find(num[i]+num[j]) if x == -1: return False i += 1 j -= 1 return True
Merge Sort Complexity: O(n log(n))
def merge_sort(arr): """ Merge Sort Complexity: O(n log(n)) """ # Our recursive base case if len(arr) <= 1: return arr mid = len(arr) // 2 # Perform merge_sort recursively on both halves left, right = merge_sort(arr[:mid]), merge_sort(arr[mid:]) # Merge each side togethe...
Merge helper Complexity: O(n)
def merge(left, right, merged): """ Merge helper Complexity: O(n) """ left_cursor, right_cursor = 0, 0 while left_cursor < len(left) and right_cursor < len(right): # Sort each one and place into the result if left[left_cursor] <= right[right_cursor]: merged[left_curs...
Bucket Sort Complexity: O(n^2) The complexity is dominated by nextSort
def bucket_sort(arr): ''' Bucket Sort Complexity: O(n^2) The complexity is dominated by nextSort ''' # The number of buckets and make buckets num_buckets = len(arr) buckets = [[] for bucket in range(num_buckets)] # Assign values into bucket_sort for value in arr: inde...
Initialize max heap with first k points. Python does not support a max heap; thus we can use the default min heap where the keys (distance) are negated.
def k_closest(points, k, origin=(0, 0)): # Time: O(k+(n-k)logk) # Space: O(k) """Initialize max heap with first k points. Python does not support a max heap; thus we can use the default min heap where the keys (distance) are negated. """ heap = [(-distance(p, origin), p) for p in points[:k]] ...
:type head: ListNode :rtype: ListNode
def reverse_list(head): """ :type head: ListNode :rtype: ListNode """ if not head or not head.next: return head prev = None while head: current = head head = head.next current.next = prev prev = current return prev
:type head: ListNode :rtype: ListNode
def reverse_list_recursive(head): """ :type head: ListNode :rtype: ListNode """ if head is None or head.next is None: return head p = head.next head.next = None revrest = reverse_list_recursive(p) p.next = head return revrest
:type root: TreeNode :type sum: int :rtype: bool
def has_path_sum(root, sum): """ :type root: TreeNode :type sum: int :rtype: bool """ if root is None: return False if root.left is None and root.right is None and root.val == sum: return True sum -= root.val return has_path_sum(root.left, sum) or has_path_sum(root.ri...
:type n: int :type base: int :rtype: str
def int_to_base(n, base): """ :type n: int :type base: int :rtype: str """ is_negative = False if n == 0: return '0' elif n < 0: is_negative = True n *= -1 digit = string.digits + string.ascii_uppercase res = '' while n > 0: res += ...
Note : You can use int() built-in function instread of this. :type s: str :type base: int :rtype: int
def base_to_int(s, base): """ Note : You can use int() built-in function instread of this. :type s: str :type base: int :rtype: int """ digit = {} for i,c in enumerate(string.digits + string.ascii_uppercase): digit[c] = i multiplier = 1 res = 0 fo...
:type head: Node :rtype: bool
def is_cyclic(head): """ :type head: Node :rtype: bool """ if not head: return False runner = head walker = head while runner.next and runner.next.next: runner = runner.next.next walker = walker.next if runner == walker: return True return ...
:type s: str :rtype: str
def decode_string(s): """ :type s: str :rtype: str """ stack = []; cur_num = 0; cur_string = '' for c in s: if c == '[': stack.append((cur_string, cur_num)) cur_string = '' cur_num = 0 elif c == ']': prev_string, num = stack.pop() ...
A slightly more Pythonic approach with a recursive generator
def palindromic_substrings_iter(s): """ A slightly more Pythonic approach with a recursive generator """ if not s: yield [] return for i in range(len(s), 0, -1): sub = s[:i] if sub == sub[::-1]: for rest in palindromic_substrings_iter(s[i:]): ...
:type s: str :type t: str :rtype: bool
def is_isomorphic(s, t): """ :type s: str :type t: str :rtype: bool """ if len(s) != len(t): return False dict = {} set_value = set() for i in range(len(s)): if s[i] not in dict: if t[i] in set_value: return False dict[s[i]] = t...
Calculate operation result n2 Number: Number 2 n1 Number: Number 1 operator Char: Operation to calculate
def calc(n2, n1, operator): """ Calculate operation result n2 Number: Number 2 n1 Number: Number 1 operator Char: Operation to calculate """ if operator == '-': return n1 - n2 elif operator == '+': return n1 + n2 elif operator == '*': return n1 * n2 elif operator == '...
Apply operation to the first 2 items of the output queue op_stack Deque (reference) out_stack Deque (reference)
def apply_operation(op_stack, out_stack): """ Apply operation to the first 2 items of the output queue op_stack Deque (reference) out_stack Deque (reference) """ out_stack.append(calc(out_stack.pop(), out_stack.pop(), op_stack.pop()))
Return array of parsed tokens in the expression expression String: Math expression to parse in infix notation
def parse(expression): """ Return array of parsed tokens in the expression expression String: Math expression to parse in infix notation """ result = [] current = "" for i in expression: if i.isdigit() or i == '.': current += i else: if le...
Calculate result of expression expression String: The expression type Type (optional): Number type [int, float]
def evaluate(expression): """ Calculate result of expression expression String: The expression type Type (optional): Number type [int, float] """ op_stack = deque() # operator stack out_stack = deque() # output stack (values) tokens = parse(expression) # calls the function onl...
simple user-interface
def main(): """ simple user-interface """ print("\t\tCalculator\n\n") while True: user_input = input("expression or exit: ") if user_input == "exit": break try: print("The result is {0}".format(evaluate(user_input))) except Excep...
:type root: TreeNode :type target: float :rtype: int
def closest_value(root, target): """ :type root: TreeNode :type target: float :rtype: int """ a = root.val kid = root.left if target < a else root.right if not kid: return a b = closest_value(kid, target) return min((a,b), key=lambda x: abs(target-x))
Return list of all primes less than n, Using sieve of Eratosthenes.
def get_primes(n): """Return list of all primes less than n, Using sieve of Eratosthenes. """ if n <= 0: raise ValueError("'n' must be a positive integer.") # If x is even, exclude x from list (-1): sieve_size = (n // 2 - 1) if n % 2 == 0 else (n // 2) sieve = [True for _ in range(si...
returns a list with the permuations.
def permute(elements): """ returns a list with the permuations. """ if len(elements) <= 1: return [elements] else: tmp = [] for perm in permute(elements[1:]): for i in range(len(elements)): tmp.append(perm[:i] + elements[0:1] + perm[i:]) ...
iterator: returns a perumation by each call.
def permute_iter(elements): """ iterator: returns a perumation by each call. """ if len(elements) <= 1: yield elements else: for perm in permute_iter(elements[1:]): for i in range(len(elements)): yield perm[:i] + elements[0:1] + perm[i:]
Extended GCD algorithm. Return s, t, g such that a * s + b * t = GCD(a, b) and s and t are co-prime.
def extended_gcd(a, b): """Extended GCD algorithm. Return s, t, g such that a * s + b * t = GCD(a, b) and s and t are co-prime. """ old_s, s = 1, 0 old_t, t = 0, 1 old_r, r = a, b while r != 0: quotient = old_r / r old_r, r = r, old_r - quotient * r ...
type root: root class
def bin_tree_to_list(root): """ type root: root class """ if not root: return root root = bin_tree_to_list_util(root) while root.left: root = root.left return root
:type num: str :type target: int :rtype: List[str]
def add_operators(num, target): """ :type num: str :type target: int :rtype: List[str] """ def dfs(res, path, num, target, pos, prev, multed): if pos == len(num): if target == prev: res.append(path) return for i in range(pos, len(num)): ...
internal library initializer.
def _init_rabit(): """internal library initializer.""" if _LIB is not None: _LIB.RabitGetRank.restype = ctypes.c_int _LIB.RabitGetWorldSize.restype = ctypes.c_int _LIB.RabitIsDistributed.restype = ctypes.c_int _LIB.RabitVersionNumber.restype = ctypes.c_int
Initialize the rabit library with arguments
def init(args=None): """Initialize the rabit library with arguments""" if args is None: args = [] arr = (ctypes.c_char_p * len(args))() arr[:] = args _LIB.RabitInit(len(arr), arr)
Print message to the tracker. This function can be used to communicate the information of the progress to the tracker Parameters ---------- msg : str The message to be printed to tracker.
def tracker_print(msg): """Print message to the tracker. This function can be used to communicate the information of the progress to the tracker Parameters ---------- msg : str The message to be printed to tracker. """ if not isinstance(msg, STRING_TYPES): msg = str(msg...
Get the processor name. Returns ------- name : str the name of processor(host)
def get_processor_name(): """Get the processor name. Returns ------- name : str the name of processor(host) """ mxlen = 256 length = ctypes.c_ulong() buf = ctypes.create_string_buffer(mxlen) _LIB.RabitGetProcessorName(buf, ctypes.byref(length), mxlen) return buf.value
Broadcast object from one node to all other nodes. Parameters ---------- data : any type that can be pickled Input data, if current rank does not equal root, this can be None root : int Rank of the node to broadcast data from. Returns ------- object : int the result...
def broadcast(data, root): """Broadcast object from one node to all other nodes. Parameters ---------- data : any type that can be pickled Input data, if current rank does not equal root, this can be None root : int Rank of the node to broadcast data from. Returns ------- ...
Normalize UNIX path to a native path.
def normpath(path): """Normalize UNIX path to a native path.""" normalized = os.path.join(*path.split("/")) if os.path.isabs(path): return os.path.abspath("/") + normalized else: return normalized
internal training function
def _train_internal(params, dtrain, num_boost_round=10, evals=(), obj=None, feval=None, xgb_model=None, callbacks=None): """internal training function""" callbacks = [] if callbacks is None else callbacks evals = list(evals) if isinstance(param...
Train a booster with given parameters. Parameters ---------- params : dict Booster params. dtrain : DMatrix Data to be trained. num_boost_round: int Number of boosting iterations. evals: list of pairs (DMatrix, string) List of items to be evaluated during trainin...
def train(params, dtrain, num_boost_round=10, evals=(), obj=None, feval=None, maximize=False, early_stopping_rounds=None, evals_result=None, verbose_eval=True, xgb_model=None, callbacks=None, learning_rates=None): # pylint: disable=too-many-statements,too-many-branches, attribute-defined-outside...
Make an n-fold list of CVPack from random indices.
def mknfold(dall, nfold, param, seed, evals=(), fpreproc=None, stratified=False, folds=None, shuffle=True): """ Make an n-fold list of CVPack from random indices. """ evals = list(evals) np.random.seed(seed) if stratified is False and folds is None: # Do standard k-fold cros...
Aggregate cross-validation results. If verbose_eval is true, progress is displayed in every call. If verbose_eval is an integer, progress will only be displayed every `verbose_eval` trees, tracked via trial.
def aggcv(rlist): # pylint: disable=invalid-name """ Aggregate cross-validation results. If verbose_eval is true, progress is displayed in every call. If verbose_eval is an integer, progress will only be displayed every `verbose_eval` trees, tracked via trial. """ cvmap = {} idx = r...
Cross-validation with given parameters. Parameters ---------- params : dict Booster params. dtrain : DMatrix Data to be trained. num_boost_round : int Number of boosting iterations. nfold : int Number of folds in CV. stratified : bool Perform stratifi...
def cv(params, dtrain, num_boost_round=10, nfold=3, stratified=False, folds=None, metrics=(), obj=None, feval=None, maximize=False, early_stopping_rounds=None, fpreproc=None, as_pandas=True, verbose_eval=None, show_stdv=True, seed=0, callbacks=None, shuffle=True): # pylint: disable = invalid-na...
Update the boosters for one iteration
def update(self, iteration, fobj): """"Update the boosters for one iteration""" self.bst.update(self.dtrain, iteration, fobj)
Evaluate the CVPack for one iteration.
def eval(self, iteration, feval): """"Evaluate the CVPack for one iteration.""" return self.bst.eval_set(self.watchlist, iteration, feval)
return whether the current callback context is cv or train
def _get_callback_context(env): """return whether the current callback context is cv or train""" if env.model is not None and env.cvfolds is None: context = 'train' elif env.model is None and env.cvfolds is not None: context = 'cv' return context
format metric string
def _fmt_metric(value, show_stdv=True): """format metric string""" if len(value) == 2: return '%s:%g' % (value[0], value[1]) if len(value) == 3: if show_stdv: return '%s:%g+%g' % (value[0], value[1], value[2]) return '%s:%g' % (value[0], value[1]) raise ValueError("wr...
Create a callback that print evaluation result. We print the evaluation results every **period** iterations and on the first and the last iterations. Parameters ---------- period : int The period to log the evaluation results show_stdv : bool, optional Whether show stdv if pr...
def print_evaluation(period=1, show_stdv=True): """Create a callback that print evaluation result. We print the evaluation results every **period** iterations and on the first and the last iterations. Parameters ---------- period : int The period to log the evaluation results show...
Create a call back that records the evaluation history into **eval_result**. Parameters ---------- eval_result : dict A dictionary to store the evaluation results. Returns ------- callback : function The requested callback function.
def record_evaluation(eval_result): """Create a call back that records the evaluation history into **eval_result**. Parameters ---------- eval_result : dict A dictionary to store the evaluation results. Returns ------- callback : function The requested callback function. ...
Reset learning rate after iteration 1 NOTE: the initial learning rate will still take in-effect on first iteration. Parameters ---------- learning_rates: list or function List of learning rate for each boosting round or a customized function that calculates eta in terms of curr...
def reset_learning_rate(learning_rates): """Reset learning rate after iteration 1 NOTE: the initial learning rate will still take in-effect on first iteration. Parameters ---------- learning_rates: list or function List of learning rate for each boosting round or a customized funct...
Create a callback that activates early stoppping. Validation error needs to decrease at least every **stopping_rounds** round(s) to continue training. Requires at least one item in **evals**. If there's more than one, will use the last. Returns the model from the last iteration (not the best one). ...
def early_stop(stopping_rounds, maximize=False, verbose=True): """Create a callback that activates early stoppping. Validation error needs to decrease at least every **stopping_rounds** round(s) to continue training. Requires at least one item in **evals**. If there's more than one, will use the la...
Run the doxygen make command in the designated folder.
def run_doxygen(folder): """Run the doxygen make command in the designated folder.""" try: retcode = subprocess.call("cd %s; make doxygen" % folder, shell=True) if retcode < 0: sys.stderr.write("doxygen terminated by signal %s" % (-retcode)) except OSError as e: sys.stderr.write("doxygen executi...
Decorate an objective function Converts an objective function using the typical sklearn metrics signature so that it is usable with ``xgboost.training.train`` Parameters ---------- func: callable Expects a callable with signature ``func(y_true, y_pred)``: y_true: array_like of sha...
def _objective_decorator(func): """Decorate an objective function Converts an objective function using the typical sklearn metrics signature so that it is usable with ``xgboost.training.train`` Parameters ---------- func: callable Expects a callable with signature ``func(y_true, y_pred...
Set the parameters of this estimator. Modification of the sklearn method to allow unknown kwargs. This allows using the full range of xgboost parameters that are not defined as member variables in sklearn grid search. Returns ------- self
def set_params(self, **params): """Set the parameters of this estimator. Modification of the sklearn method to allow unknown kwargs. This allows using the full range of xgboost parameters that are not defined as member variables in sklearn grid search. Returns ------- ...
Get parameters.
def get_params(self, deep=False): """Get parameters.""" params = super(XGBModel, self).get_params(deep=deep) if isinstance(self.kwargs, dict): # if kwargs is a dict, update params accordingly params.update(self.kwargs) if params['missing'] is np.nan: params['miss...
Get xgboost type parameters.
def get_xgb_params(self): """Get xgboost type parameters.""" xgb_params = self.get_params() random_state = xgb_params.pop('random_state') if 'seed' in xgb_params and xgb_params['seed'] is not None: warnings.warn('The seed parameter is deprecated as of version .6.' ...
Load the model from a file. The model is loaded from an XGBoost internal binary format which is universal among the various XGBoost interfaces. Auxiliary attributes of the Python Booster object (such as feature names) will not be loaded. Label encodings (text labels to numeric labels) w...
def load_model(self, fname): """ Load the model from a file. The model is loaded from an XGBoost internal binary format which is universal among the various XGBoost interfaces. Auxiliary attributes of the Python Booster object (such as feature names) will not be loaded. ...
Fit the gradient boosting model Parameters ---------- X : array_like Feature matrix y : array_like Labels sample_weight : array_like instance weights eval_set : list, optional A list of (X, y) tuple pairs to use as a valida...
def fit(self, X, y, sample_weight=None, eval_set=None, eval_metric=None, early_stopping_rounds=None, verbose=True, xgb_model=None, sample_weight_eval_set=None, callbacks=None): # pylint: disable=missing-docstring,invalid-name,attribute-defined-outside-init """ Fit the gra...
Predict with `data`. .. note:: This function is not thread safe. For each booster object, predict can only be called from one thread. If you want to run prediction using multiple thread, call ``xgb.copy()`` to make copies of model object and then call ``predict()``. .. n...
def predict(self, data, output_margin=False, ntree_limit=None, validate_features=True): """ Predict with `data`. .. note:: This function is not thread safe. For each booster object, predict can only be called from one thread. If you want to run prediction using multiple thr...
Return the predicted leaf every tree for each sample. Parameters ---------- X : array_like, shape=[n_samples, n_features] Input features matrix. ntree_limit : int Limit number of trees in the prediction; defaults to 0 (use all trees). Returns --...
def apply(self, X, ntree_limit=0): """Return the predicted leaf every tree for each sample. Parameters ---------- X : array_like, shape=[n_samples, n_features] Input features matrix. ntree_limit : int Limit number of trees in the prediction; defaults to ...
Feature importances property .. note:: Feature importance is defined only for tree boosters Feature importance is only defined when the decision tree model is chosen as base learner (`booster=gbtree`). It is not defined for other base learner types, such as linear learners ...
def feature_importances_(self): """ Feature importances property .. note:: Feature importance is defined only for tree boosters Feature importance is only defined when the decision tree model is chosen as base learner (`booster=gbtree`). It is not defined for other base...
Coefficients property .. note:: Coefficients are defined only for linear learners Coefficients are only defined when the linear model is chosen as base learner (`booster=gblinear`). It is not defined for other base learner types, such as tree learners (`booster=gbtree`). ...
def coef_(self): """ Coefficients property .. note:: Coefficients are defined only for linear learners Coefficients are only defined when the linear model is chosen as base learner (`booster=gblinear`). It is not defined for other base learner types, such as...
Intercept (bias) property .. note:: Intercept is defined only for linear learners Intercept (bias) is only defined when the linear model is chosen as base learner (`booster=gblinear`). It is not defined for other base learner types, such as tree learners (`booster=gbtree`)....
def intercept_(self): """ Intercept (bias) property .. note:: Intercept is defined only for linear learners Intercept (bias) is only defined when the linear model is chosen as base learner (`booster=gblinear`). It is not defined for other base learner types, such ...
Predict with `data`. .. note:: This function is not thread safe. For each booster object, predict can only be called from one thread. If you want to run prediction using multiple thread, call ``xgb.copy()`` to make copies of model object and then call ``predict()``. .. n...
def predict(self, data, output_margin=False, ntree_limit=None, validate_features=True): """ Predict with `data`. .. note:: This function is not thread safe. For each booster object, predict can only be called from one thread. If you want to run prediction using multiple thr...
Predict the probability of each `data` example being of a given class. .. note:: This function is not thread safe For each booster object, predict can only be called from one thread. If you want to run prediction using multiple thread, call ``xgb.copy()`` to make copies of ...
def predict_proba(self, data, ntree_limit=None, validate_features=True): """ Predict the probability of each `data` example being of a given class. .. note:: This function is not thread safe For each booster object, predict can only be called from one thread. If you wan...
Fit the gradient boosting model Parameters ---------- X : array_like Feature matrix y : array_like Labels group : array_like group size of training data sample_weight : array_like group weights .. note:: Weight...
def fit(self, X, y, group, sample_weight=None, eval_set=None, sample_weight_eval_set=None, eval_group=None, eval_metric=None, early_stopping_rounds=None, verbose=False, xgb_model=None, callbacks=None): # pylint: disable = attribute-defined-outside-init,arguments-differ """ ...
Convert a list of Python str to C pointer Parameters ---------- data : list list of str
def from_pystr_to_cstr(data): """Convert a list of Python str to C pointer Parameters ---------- data : list list of str """ if not isinstance(data, list): raise NotImplementedError pointers = (ctypes.c_char_p * len(data))() if PY3: data = [bytes(d, 'utf-8') for...
Revert C pointer to Python str Parameters ---------- data : ctypes pointer pointer to data length : ctypes pointer pointer to length of data
def from_cstr_to_pystr(data, length): """Revert C pointer to Python str Parameters ---------- data : ctypes pointer pointer to data length : ctypes pointer pointer to length of data """ if PY3: res = [] for i in range(length.value): try: ...
Load xgboost Library.
def _load_lib(): """Load xgboost Library.""" lib_paths = find_lib_path() if not lib_paths: return None try: pathBackup = os.environ['PATH'].split(os.pathsep) except KeyError: pathBackup = [] lib_success = False os_error_list = [] for lib_path in lib_paths: ...
Convert a ctypes pointer array to a numpy array.
def ctypes2numpy(cptr, length, dtype): """Convert a ctypes pointer array to a numpy array. """ NUMPY_TO_CTYPES_MAPPING = { np.float32: ctypes.c_float, np.uint32: ctypes.c_uint, } if dtype not in NUMPY_TO_CTYPES_MAPPING: raise RuntimeError('Supported types: {}'.format(NUMPY_TO...
Convert ctypes pointer to buffer type.
def ctypes2buffer(cptr, length): """Convert ctypes pointer to buffer type.""" if not isinstance(cptr, ctypes.POINTER(ctypes.c_char)): raise RuntimeError('expected char pointer') res = bytearray(length) rptr = (ctypes.c_char * length).from_buffer(res) if not ctypes.memmove(rptr, cptr, length)...
Convert a python string to c array.
def c_array(ctype, values): """Convert a python string to c array.""" if isinstance(values, np.ndarray) and values.dtype.itemsize == ctypes.sizeof(ctype): return (ctype * len(values)).from_buffer_copy(values) return (ctype * len(values))(*values)
Extract internal data from pd.DataFrame for DMatrix data
def _maybe_pandas_data(data, feature_names, feature_types): """ Extract internal data from pd.DataFrame for DMatrix data """ if not isinstance(data, DataFrame): return data, feature_names, feature_types data_dtypes = data.dtypes if not all(dtype.name in PANDAS_DTYPE_MAPPER for dtype in data_dt...
Validate feature names and types if data table
def _maybe_dt_data(data, feature_names, feature_types): """ Validate feature names and types if data table """ if not isinstance(data, DataTable): return data, feature_names, feature_types data_types_names = tuple(lt.name for lt in data.ltypes) bad_fields = [data.names[i] ...
Extract numpy array from single column data table
def _maybe_dt_array(array): """ Extract numpy array from single column data table """ if not isinstance(array, DataTable) or array is None: return array if array.shape[1] > 1: raise ValueError('DataTable for label or weight cannot have multiple columns') # below requires new dt version...
Initialize data from a CSR matrix.
def _init_from_csr(self, csr): """ Initialize data from a CSR matrix. """ if len(csr.indices) != len(csr.data): raise ValueError('length mismatch: {} vs {}'.format(len(csr.indices), len(csr.data))) handle = ctypes.c_void_p() _check_call(_LIB.XGDMatrixCreateFro...
Initialize data from a CSC matrix.
def _init_from_csc(self, csc): """ Initialize data from a CSC matrix. """ if len(csc.indices) != len(csc.data): raise ValueError('length mismatch: {} vs {}'.format(len(csc.indices), len(csc.data))) handle = ctypes.c_void_p() _check_call(_LIB.XGDMatrixCreateFro...
Initialize data from a 2-D numpy matrix. If ``mat`` does not have ``order='C'`` (aka row-major) or is not contiguous, a temporary copy will be made. If ``mat`` does not have ``dtype=numpy.float32``, a temporary copy will be made. So there could be as many as two temporary data copies;...
def _init_from_npy2d(self, mat, missing, nthread): """ Initialize data from a 2-D numpy matrix. If ``mat`` does not have ``order='C'`` (aka row-major) or is not contiguous, a temporary copy will be made. If ``mat`` does not have ``dtype=numpy.float32``, a temporary copy will be...
Initialize data from a datatable Frame.
def _init_from_dt(self, data, nthread): """ Initialize data from a datatable Frame. """ ptrs = (ctypes.c_void_p * data.ncols)() if hasattr(data, "internal") and hasattr(data.internal, "column"): # datatable>0.8.0 for icol in range(data.ncols): ...
Set float type property into the DMatrix. Parameters ---------- field: str The field name of the information data: numpy array The array of data to be set
def set_float_info(self, field, data): """Set float type property into the DMatrix. Parameters ---------- field: str The field name of the information data: numpy array The array of data to be set """ if getattr(data, 'base', None) is not...
Set float type property into the DMatrix for numpy 2d array input Parameters ---------- field: str The field name of the information data: numpy array The array of data to be set
def set_float_info_npy2d(self, field, data): """Set float type property into the DMatrix for numpy 2d array input Parameters ---------- field: str The field name of the information data: numpy array The array of data to be set """ ...
Set uint type property into the DMatrix. Parameters ---------- field: str The field name of the information data: numpy array The array of data to be set
def set_uint_info(self, field, data): """Set uint type property into the DMatrix. Parameters ---------- field: str The field name of the information data: numpy array The array of data to be set """ if getattr(data, 'base', None) is not N...
Save DMatrix to an XGBoost buffer. Saved binary can be later loaded by providing the path to :py:func:`xgboost.DMatrix` as input. Parameters ---------- fname : string Name of the output buffer file. silent : bool (optional; default: True) If set, the out...
def save_binary(self, fname, silent=True): """Save DMatrix to an XGBoost buffer. Saved binary can be later loaded by providing the path to :py:func:`xgboost.DMatrix` as input. Parameters ---------- fname : string Name of the output buffer file. silent : bool...
Set group size of DMatrix (used for ranking). Parameters ---------- group : array like Group size of each group
def set_group(self, group): """Set group size of DMatrix (used for ranking). Parameters ---------- group : array like Group size of each group """ _check_call(_LIB.XGDMatrixSetGroup(self.handle, c_array(ctypes.c_uint...
Get feature names (column labels). Returns ------- feature_names : list or None
def feature_names(self): """Get feature names (column labels). Returns ------- feature_names : list or None """ if self._feature_names is None: self._feature_names = ['f{0}'.format(i) for i in range(self.num_col())] return self._feature_names
Set feature names (column labels). Parameters ---------- feature_names : list or None Labels for features. None will reset existing feature names
def feature_names(self, feature_names): """Set feature names (column labels). Parameters ---------- feature_names : list or None Labels for features. None will reset existing feature names """ if feature_names is not None: # validate feature name ...
Set feature types (column types). This is for displaying the results and unrelated to the learning process. Parameters ---------- feature_types : list or None Labels for features. None will reset existing feature names
def feature_types(self, feature_types): """Set feature types (column types). This is for displaying the results and unrelated to the learning process. Parameters ---------- feature_types : list or None Labels for features. None will reset existing feature na...
Initialize the model by load from rabit checkpoint. Returns ------- version: integer The version number of the model.
def load_rabit_checkpoint(self): """Initialize the model by load from rabit checkpoint. Returns ------- version: integer The version number of the model. """ version = ctypes.c_int() _check_call(_LIB.XGBoosterLoadRabitCheckpoint( self.hand...
Get attribute string from the Booster. Parameters ---------- key : str The key to get attribute from. Returns ------- value : str The attribute value of the key, returns None if attribute do not exist.
def attr(self, key): """Get attribute string from the Booster. Parameters ---------- key : str The key to get attribute from. Returns ------- value : str The attribute value of the key, returns None if attribute do not exist. """ ...
Get attributes stored in the Booster as a dictionary. Returns ------- result : dictionary of attribute_name: attribute_value pairs of strings. Returns an empty dict if there's no attributes.
def attributes(self): """Get attributes stored in the Booster as a dictionary. Returns ------- result : dictionary of attribute_name: attribute_value pairs of strings. Returns an empty dict if there's no attributes. """ length = c_bst_ulong() sarr = ...
Set the attribute of the Booster. Parameters ---------- **kwargs The attributes to set. Setting a value to None deletes an attribute.
def set_attr(self, **kwargs): """Set the attribute of the Booster. Parameters ---------- **kwargs The attributes to set. Setting a value to None deletes an attribute. """ for key, value in kwargs.items(): if value is not None: if n...
Set parameters into the Booster. Parameters ---------- params: dict/list/str list of key,value pairs, dict of key to value or simply str key value: optional value of the specified parameter, when params is str key
def set_param(self, params, value=None): """Set parameters into the Booster. Parameters ---------- params: dict/list/str list of key,value pairs, dict of key to value or simply str key value: optional value of the specified parameter, when params is str key...
Evaluate the model on mat. Parameters ---------- data : DMatrix The dmatrix storing the input. name : str, optional The name of the dataset. iteration : int, optional The current iteration number. Returns ------- res...
def eval(self, data, name='eval', iteration=0): """Evaluate the model on mat. Parameters ---------- data : DMatrix The dmatrix storing the input. name : str, optional The name of the dataset. iteration : int, optional The current ite...
Predict with data. .. note:: This function is not thread safe. For each booster object, predict can only be called from one thread. If you want to run prediction using multiple thread, call ``bst.copy()`` to make copies of model object and then call ``predict()``. .. not...
def predict(self, data, output_margin=False, ntree_limit=0, pred_leaf=False, pred_contribs=False, approx_contribs=False, pred_interactions=False, validate_features=True): """ Predict with data. .. note:: This function is not thread safe. For each boost...
Save the model to a file. The model is saved in an XGBoost internal binary format which is universal among the various XGBoost interfaces. Auxiliary attributes of the Python Booster object (such as feature_names) will not be saved. To preserve all attributes, pickle the Booster object. ...
def save_model(self, fname): """ Save the model to a file. The model is saved in an XGBoost internal binary format which is universal among the various XGBoost interfaces. Auxiliary attributes of the Python Booster object (such as feature_names) will not be saved. To pre...
Load the model from a file. The model is loaded from an XGBoost internal binary format which is universal among the various XGBoost interfaces. Auxiliary attributes of the Python Booster object (such as feature_names) will not be loaded. To preserve all attributes, pickle the Booster ob...
def load_model(self, fname): """ Load the model from a file. The model is loaded from an XGBoost internal binary format which is universal among the various XGBoost interfaces. Auxiliary attributes of the Python Booster object (such as feature_names) will not be loaded. ...
Dump model into a text or JSON file. Parameters ---------- fout : string Output file name. fmap : string, optional Name of the file containing feature map names. with_stats : bool, optional Controls whether the split statistics are output. ...
def dump_model(self, fout, fmap='', with_stats=False, dump_format="text"): """ Dump model into a text or JSON file. Parameters ---------- fout : string Output file name. fmap : string, optional Name of the file containing feature map names. ...