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' t make sense, and actually, most physicists agree with you. the big bang is a singularity, and most of us don't think singularities occur in the real universe. we expect that some quantum gravity effect will become important as we approach the big bang. however, at the moment we have no working theory of quantum grav... | https://api.stackexchange.com |
we went back in time towards the big bang? well the flrw metric makes this quantitative. if $ ( x, y, z ) $ is some point on our grid then the current distance to that point is just given by pythagoras'theorem : $ $ d ^ 2 = x ^ 2 + y ^ 2 + z ^ 2 $ $ what the flrw metric tells us is that the distance changes with time a... | https://api.stackexchange.com |
to avoid the singularity. these days it's commonly believed that some quantum gravity effect will prevent the geometry from becoming singular, though since we have no working theory of quantum gravity no one knows how this might work. so to conclude : the big bang is the zero time limit of the flrw metric, and it's a t... | https://api.stackexchange.com |
this is partly a matter of terminology, and as such, only requires that you and the person you're talking to clarify it beforehand. however, there are different topics that are more strongly associated with parallelism, concurrency, or distributed systems. parallelism is generally concerned with accomplishing a particu... | https://api.stackexchange.com |
if you apply binary search, you have $ $ \ log _ 2 ( n ) + o ( 1 ) $ $ many comparisons. if you apply ternary search, you have $ $ 2 \ cdot \ log _ 3 ( n ) + o ( 1 ) $ $ many comparisons, as in each step, you need to perform 2 comparisons to cut the search space into three parts. now if you do the math, you can observe... | https://api.stackexchange.com |
the anode is the electrode where the oxidation reaction \ begin { align } \ ce { red - > ox + e - } \ end { align } takes place while the cathode is the electrode where the reduction reaction \ begin { align } \ ce { ox + e - - > red } \ end { align } takes place. that's how cathode and anode are defined. galvanic cell... | https://api.stackexchange.com |
inclined plane. the reason is the same : water and electrons can lower their energy this way. now the external voltage source acts like two big rivers connected to waterfalls : one at a high altitude that leads towards a waterfall - that would be the minus pole - and one at a low altitude that leads away from a waterfa... | https://api.stackexchange.com |
water " that is added to it doesn't change the river much. it stays the same, unaltered so that everytime a floodgate gets opened the water from the barrier lake will drop the same distance. | https://api.stackexchange.com |
dataset will be a data frame. as i don't have forr. csv, i'll make up a small data frame for illustration : set. seed ( 1 ) dataset < - data. frame ( a = sample ( c ( na, 1 : 100 ), 1000, rep = true ), b = rnorm ( 1000 ) ) > head ( dataset ) a b 1 26 0. 07730312 2 37 - 0. 29686864 3 57 - 1. 18324224 4 91 0. 01129269 5 ... | https://api.stackexchange.com |
the difference in your timings seems to be due to the manual unrolling of the unit - stride fortran daxpy. the following timings are on a 2. 67 ghz xeon x5650, using the command. / test 1000000 10000 intel 11. 1 compilers fortran with manual unrolling : 8. 7 sec fortran w / o manual unrolling : 5. 8 sec c w / o manual ... | https://api.stackexchange.com |
sorry i don't know opencv, and this is more a pre - processing step than a complete answer : first, you don't want an edge detector. an edge detector converts transitions ( like this dark - to - light ) : into ridges ( bright lines on dark ) like this : it performs a differentiation, in other words. but in your images,... | https://api.stackexchange.com |
= image. open ( filename ). convert ('l') i = asarray ( i ) # remove dc offset i = i - average ( i ) close ('all') figure ( ) imshow ( i ) gray ( ) show ( ) title ('original') # remove slowly - varying features sigma _ 2d = 2 i = i - gaussian _ filter ( i, sigma _ 2d ) figure ( ) imshow ( i ) title ('2d filtered with %... | https://api.stackexchange.com |
a linear function fixes the origin, whereas an affine function need not do so. an affine function is the composition of a linear function with a translation, so while the linear part fixes the origin, the translation can map it somewhere else. linear functions between vector spaces preserve the vector space structure (... | https://api.stackexchange.com |
i think that documentation for scientific software can be divided into three categories, all of which are necessary for full understanding. the easiest and most common is individual method documentation. there are many systems for this. you mention doxygen, python has pydoc, and in petsc we have our own package sowing ... | https://api.stackexchange.com |
i am not a kineticist, and my quantum chemistry is long, long out of date, but what i was about to say was that i'd guess the reason the " effect " is " unsolved " is that it's not real. that is, it is not a property of a single reactant while disregarding its environment ( gas phase, solvent interactions ). then i saw... | https://api.stackexchange.com |
what ’ s the proper soldering iron temperature for standard. 031 " 60 / 40 solder? there is no proper soldering iron temperature just for a given type of solder - the iron temperature should be set for both the component and the solder. when soldering surface mount components, a small tip and 600f ( 315c ) should be su... | https://api.stackexchange.com |
samtools has a subsampling option : - s float : integer part is used to seed the random number generator [ 0 ]. part after the decimal point sets the fraction of templates / pairs to subsample [ no subsampling ] samtools view - bs 42. 1 in. bam > subsampled. bam will subsample 10 percent mapped reads with 42 as the see... | https://api.stackexchange.com |
the laplace and fourier transforms are continuous ( integral ) transforms of continuous functions. the laplace transform maps a function \ $ f ( t ) \ $ to a function \ $ f ( s ) \ $ of the complex variable s, where \ $ s = \ sigma + j \ omega \ $. since the derivative \ $ \ dot f ( t ) = \ frac { df ( t ) } { dt } \ $... | https://api.stackexchange.com |
a guy is flying in a hot air balloon and he's lost. so he lowers himself over a field and shouts to a guy on the ground : " can you tell me where i am, and which way i'm headed? " " sure! you're at 43 degrees, 12 minutes, 21. 2 seconds north ; 123 degrees, 8 minutes, 12. 8 seconds west. you're at 212 meters above sea l... | https://api.stackexchange.com |
i've decided to tackle this question in a somewhat different manner. instead of giving the chemical intuition behind it, i wanted to check for myself if the mathematics actually work out. as far as i understand, this isn't done often, so that's why i wanted to try it, even though it may not make the clearest answer. it... | https://api.stackexchange.com |
{ boh } $ or $ \ ce { b ^ + } $ ) is $ n _ \ text { b } = c _ \ text { b } v _ \ text { b } $. notice that at the equivalence point, $ n _ \ text { a } = n _ \ text { b } $ and therefore $ c _ \ text { a } v _ \ text { a } = c _ \ text { b } v _ \ text { b } $ ; this will be important later. we will assume that volumes... | https://api.stackexchange.com |
k _ \ text { w } } { k _ \ text { b } \ ce { [ h ^ + ] } } $ $ $ $ \ ce { [ a ^ - ] } = \ frac { c _ \ text { a } v _ \ text { a } } { v _ \ text { a } + v _ \ text { b } } \ left ( \ frac { k _ \ text { a } } { k _ \ text { a } + \ ce { [ h ^ + ] } } \ right ) $ $ $ $ \ ce { [ b ^ + ] } = \ frac { c _ \ text { b } v _... | https://api.stackexchange.com |
} { v _ \ text { a } + v _ \ text { b } } \ frac { k _ \ text { a } } { k _ \ text { b } } k _ \ text { w } + \ frac { k ^ 2 _ \ text { w } } { k _ \ text { b } } \ right ) \ ce { [ h ^ + ] } - \ frac { k _ \ text { a } } { k _ \ text { b } } k ^ 2 _ \ text { w } = 0 $ $ now, this equation sure looks intimidating, but ... | https://api.stackexchange.com |
ce { a } - k _ \ ce { w } \ right ) \ ce { [ h ^ + ] } - k _ \ ce { a } k _ \ ce { w } = 0 $ $ for a strong acid and weak base ( $ k _ \ text { a } \ gg 1 $ ), you can divide both sides of the equation by $ k _ \ text { a } $, and now all terms with $ k _ \ text { a } $ in the denominator get cancelled out, leaving : s... | https://api.stackexchange.com |
right ) \ ce { [ h ^ + ] } - k _ \ ce { w } = 0 $ $ it would be enlightening to draw some example graphs for each equation, but wolfram alpha only seems to be able to handle the last one, as the others require more than the standard computation time to display. still, considering the titration of $ 1 ~ \ text { l } $ o... | https://api.stackexchange.com |
complicated looking fraction, but with very interesting properties. the numerator is not too important, it's the denominator where the magic happens. notice that we have a sum of two terms ( $ 2 ( v _ \ ce { a } + v _ \ ce { b } ) \ ce { [ h ^ + ] } $ and $ ( c _ \ ce { b } v _ \ ce { b } - c _ \ ce { a } v _ \ ce { a ... | https://api.stackexchange.com |
^ + ] } } { \ ce { d } v _ \ ce { b } } = \ frac { - \ frac { v _ \ ce { a } } { ( v _ \ ce { a } + v _ \ ce { b } ) ^ 2 } \ ce { [ h ^ + ] } ( c _ \ ce { b } \ ce { [ h ^ + ] } - c _ \ ce { b } k _ \ ce { a } + c _ \ ce { a } k _ \ ce { a } ) } { 3 \ ce { [ h ^ + ] ^ 2 + 2 [ h ^ + ] } \ left ( k _ \ ce { a } + \ frac ... | https://api.stackexchange.com |
here is a 97 - line example of solving a simple multivariate pde using finite difference methods, contributed by prof. david ketcheson, from the py4sci repository i maintain. for more complicated problems where you need to handle shocks or conservation in a finite - volume discretization, i recommend looking at pyclaw,... | https://api.stackexchange.com |
v * * 2 ) + v * ( 1 - tau2 * u ) ; def g ( u, v ) : return beta * v * ( 1 + alpha * tau1 / beta * u * v ) + u * ( gamma + tau2 * v ) ; def five _ pt _ laplacian ( m, a, b ) : " " " construct a matrix that applies the 5 - point laplacian discretization " " " e = np. ones ( m * * 2 ) e2 = ( [ 0 ] + [ 1 ] * ( m - 1 ) ) * ... | https://api.stackexchange.com |
colorbar ; plt. axis ('image') ; plt. draw ( ) u = u. reshape ( - 1 ) v = v. reshape ( - 1 ) a = five _ pt _ laplacian _ sparse ( m, - 1., 1. ) ; ii = eye ( m * m, m * m ) t = 0. dt = h / delta / 5. ; plt. ion ( ) # now step forward in time for k in range ( 120 ) : # simple ( 1st - order ) operator splitting : u = lina... | https://api.stackexchange.com |
summary spi is faster. i2c is more complex and not as easy to use if your microcontroller doesn't have an i2c controller. i2c only requires 2 lines. i2c is a bus system with bidirectional data on the sda line. spi is a point - to - point connection with data in and data out on separate lines ( mosi and miso ). essentia... | https://api.stackexchange.com |
communication data is only allowed to change when the clock is low. this start sequence synchronizes each communication. since the communication includes the addressing only two lines are required for any number of devices ( up to 127 ). edit it's obvious that the data line is bidirectional, but it's worth noting that ... | https://api.stackexchange.com |
arbitrary record access in constant time to get a random record in constant time, it is sufficient to get an arbitrary record in constant time. i have two solutions here : one with tabix and one with grabix. i think the grabix solution is more elegant, but i am keeping the tabix solution below because tabix is a more m... | https://api.stackexchange.com |
keep tabix happy : gzip - dc input. fastq. gz | paste - - - - | nl | sed's / ^ * / /'| sed's / ^ / dummy \ t /'| bgzip - c > output. fastq. gz tabix - s 1 - b 2 - e 2 output. fastq. gz # now retrieve the 5th record ( 1 - based ) in log ( n ) time tabix output. fastq. gz dummy : 5 - 5 # this command will retrieve the 5t... | https://api.stackexchange.com |
_ read. py disclaimer please note that os. system calls a system shell and is vulnerable to shell injection vulnerabilities. if you are writing production code, then you probably want to take extra precautions. thanks to chris _ rands for raising this issue. | https://api.stackexchange.com |
check into generatingfunctionology by herbert wilf. from the linked ( author's ) site, the second edition is available for downloading as a pdf. there is also a link to the third edition, available for purchase. it's a very helpful, useful, readable, fun, ( and short! ) book that a student could conceivably cover over ... | https://api.stackexchange.com |
this answer is intended to clear up some misconceptions about resonance which have come up many times on this site. resonance is a part of valence bond theory which is used to describe delocalised electron systems in terms of contributing structures, each only involving 2 - centre - 2 - electron bonds. it is a concept ... | https://api.stackexchange.com |
filtfilt is zero - phase filtering, which doesn't shift the signal as it filters. since the phase is zero at all frequencies, it is also linear - phase. filtering backwards in time requires you to predict the future, so it can't be used in " online " real - life applications, only for offline processing of recordings o... | https://api.stackexchange.com |
np. cumsum ( randn ( 800 ) ) # brownian noise sig _ ff = signal. filtfilt ( b, a, sig ) sig _ lf = signal. lfilter ( b, a, signal. lfilter ( b, a, sig ) ) plt. subplot ( 2, 1, 2 ) plt. plot ( sig, color ='silver ', label ='original') plt. plot ( sig _ ff, color ='# 3465a4 ', label ='filtfilt') plt. plot ( sig _ lf, col... | https://api.stackexchange.com |
for fastq : seqtk fqchk in. fq | head - 2 it gives you percentage of " n " bases, not the exact count, though. for fasta : seqtk comp in. fa | awk'{ x + = $ 9 } end { print x }'this command line also works with fastq, but it will be slower as awk is slow. edit : ok, based on @ bach's reminder, here we go ( you need kse... | https://api.stackexchange.com |
4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4 } ; int main ( int... | https://api.stackexchange.com |
0 ; } it works for both fasta / q and gzip'ed fasta / q. the following uses seqan : # include < seqan / seq _ io. h > using namespace seqan ; int main ( int argc, char * argv [ ] ) { if ( argc = = 1 ) { std : : cerr < < " usage : count - n < in. fastq > " < < std : : endl ; return 1 ; } std : : ios : : sync _ with _ st... | https://api.stackexchange.com |
according to current nomenclature rules, $ \ ce { h3n } $ would be correct and acceptable. however some chemical formulas, like $ \ ce { nh3 } $ for ammonia, that were in use long before the rules came out, are still accepted today. | https://api.stackexchange.com |
joblib does what you want. the basic usage pattern is : from joblib import parallel, delayed def myfun ( arg ) : do _ stuff return result results = parallel ( n _ jobs = - 1, verbose = verbosity _ level, backend = " threading " ) ( map ( delayed ( myfun ), arg _ instances ) ) where arg _ instances is list of values for... | https://api.stackexchange.com |
to quote from the answer to “ traversals from the root in avl trees and red black trees ” question for some kinds of binary search trees, including red - black trees but not avl trees, the " fixes " to the tree can fairly easily be predicted on the way down and performed during a single top - down pass, making the seco... | https://api.stackexchange.com |
i agree that a turing machine can do " all the possible mathematical problems ". well, you shouldn't, because it's not true. for example, turing machines cannot determine if polynomials with integer coefficients have integer solutions ( hilbert's tenth problem ). is turing machine “ by definition ” the most powerful ma... | https://api.stackexchange.com |
j. m's comment is right : you can find an interpolating polynomial and differentiate it. there are other ways of deriving such formulas ; typically, they all lead to solving a van der monde system for the coefficients. this approach is problematic when the finite difference stencil includes a large number of points, be... | https://api.stackexchange.com |
if $ p $ is an infinitely differentiable function such that for each $ x $, there is an $ n $ with $ p ^ { ( n ) } ( x ) = 0 $, then $ p $ is a polynomial. ( note $ n $ depends on $ x $. ) see the discussion in math overflow. | https://api.stackexchange.com |
well, a dfa is just a turing machine that's only allowed to move to the right and that must accept or reject as soon as it runs out of input characters. so i'm not sure one can really say that a dfa is natural but a turing machine isn't. critique of the question aside, remember that turing was working before computers ... | https://api.stackexchange.com |
you can refer to " detecting start of a loop in singly linked list ", here's an excerpt : distance travelled by slowpointer before meeting $ = x + y $ distance travelled by fastpointer before meeting $ = ( x + y + z ) + y = x + 2y + z $ since fastpointer travels with double the speed of slowpointer, and time is constan... | https://api.stackexchange.com |
first, not all processor architectures stopped at 32 registers. almost all the risc architectures that have 32 registers exposed in the instruction set actually have 32 integer registers and 32 more floating point registers ( so 64 ). ( floating point " add " uses different registers than integer " add ". ) the sparc a... | https://api.stackexchange.com |
you would need to start clocking your machine slower to accommodate the larger register file. usually in terms of total performance this is a lose. | https://api.stackexchange.com |
1. verify that your code is bug free there's a saying among writers that " all writing is re - writing " - - that is, the greater part of writing is revising. for programmers ( or at least data scientists ) the expression could be re - phrased as " all coding is debugging. " any time you're writing code, you need to ve... | https://api.stackexchange.com |
4, 4 ], stride = 4, scope ='pool1') net = slim. conv2d ( input _ image, 64, [ 5, 5 ], scope = " conv3 _ 5x5 " ) net = slim. conv2d ( input _ image, 128, [ 3, 3 ], scope = " conv4 _ 3x3 " ) net = slim. max _ pool2d ( net, [ 2, 2 ], scope ='pool2') net = slim. conv2d ( input _ image, 128, [ 3, 3 ], scope = " conv5 _ 3x3 ... | https://api.stackexchange.com |
the labels and samples separately ) ; accidentally assigning the training data as the testing data ; when using a train / test split, the model references the original, non - split data instead of the training partition or the testing partition. forgetting to scale the testing data ; scaling the testing data using the ... | https://api.stackexchange.com |
dimitris tsipras, andrew ilyas, aleksander madry 3. crawl before you walk ; walk before you run wide and deep neural networks, and neural networks with exotic wiring, are the hot thing right now in machine learning. but these networks didn't spring fully - formed into existence ; their designers built up to them from s... | https://api.stackexchange.com |
configuration choices is not really as simple as saying that one kind of configuration choice ( e. g. learning rate ) is more or less important than another ( e. g. number of units ), since all of these choices interact with all of the other choices, so one choice can do well in combination with another choice made els... | https://api.stackexchange.com |
networks are well - known ( see : why is it hard to train deep neural networks? ). additionally, neural networks have a very large number of parameters, which restricts us to solely first - order methods ( see : why is newton's method not widely used in machine learning? ). this is a very active area of research. setti... | https://api.stackexchange.com |
networks. " the marginal value of adaptive gradient methods in machine learning " by ashia c. wilson, rebecca roelofs, mitchell stern, nathan srebro, benjamin recht but on the other hand, this very recent paper proposes a new adaptive learning - rate optimizer which supposedly closes the gap between adaptive - rate met... | https://api.stackexchange.com |
it's widely observed that layer normalization and dropout are difficult to use together. since either on its own is very useful, understanding how to use both is an active area of research. " understanding the disharmony between dropout and batch normalization by variance shift " by xiang li, shuo chen, xiaolin hu, jia... | https://api.stackexchange.com |
noise is quite good ( hard to compress ), but it becomes grey when looking from far, becoming easy to compress. a good pattern would be kind of fractal, looking similar at all scales. well, there is fractal noise. i think brownian noise is fractal, looking the same as you zoom into it. wikipedia talks about adding perl... | https://api.stackexchange.com |
short answer color - blind subjects are better at detecting color - camouflaged objects. this may give color blinds an advantage in terms of spotting hidden dangers ( predators ) or finding camouflaged foods. background there are two types of red - green blindness : protanopia ( red - blind ) and deuteranopia ( green -... | https://api.stackexchange.com |
has been a recurrent one, both with respect to military camouflage and with respect to the camouflage of the natural world ( reviewed in morgan et al. ( 1992 ) outlines, rather than colors, are responsible for pattern recognition. in the military, colorblind snipers and spotters are highly valued for these reasons ( so... | https://api.stackexchange.com |
the way to think of cross - validation is as estimating the performance obtained using a method for building a model, rather than for estimating the performance of a model. if you use cross - validation to estimate the hyperparameters of a model ( the $ \ alpha $ s ) and then use those hyper - parameters to fit a model... | https://api.stackexchange.com |
you obtain an unbiased performance estimate via nested cross - validation and potentially consider penalising the cross - validation statistic to further avoid over - fitting in model selection. | https://api.stackexchange.com |
first determine the coil current when the coil is on. this is the current that will flow through the diode when the coil is switched off. in your relay, the coil current is shown as 79. 4 ma. specify a diode for at least 79. 4 ma current. in your case, a 1n4001 current rating far exceeds the requirement. the diode reve... | https://api.stackexchange.com |
sometimes men wake up with an erection in the morning. why does this happen? shortly speaking : rem ( rapid eye movement ) is one phase of sleep. during this phase, we dream and some of our neurotransmitters are shut off. this include norepinephrine, which is involved in controlling erections. norepinephrine prevents b... | https://api.stackexchange.com |
i've gathered the following from online research so far : i've used armadillo a little bit, and found the interface to be intuitive enough, and it was easy to locate binary packages for ubuntu ( and i'm assuming other linux distros ). i haven't compiled it from source, but my hope is that it wouldn't be too difficult. ... | https://api.stackexchange.com |
linear solver and eigensolver functionality. the documentation does not seem to be as polished or prominent as petsc ; trilinos seems like the sandia analog of petsc. petsc can call some of the trilinos solvers. binaries for trilinos are available for linux. blitz is a c + + object - oriented library that has linux bin... | https://api.stackexchange.com |
##rwell subroutine libraries are famous for their sparse linear algebra routines, and are free for academic users, though you have to go through this process of filling out a form and receiving an e - mail for each file that you want to download. since the subroutines often have dependencies, using one solver might req... | https://api.stackexchange.com |
you can find the various equations in this oft - cited blog post from harold pimentel. cpm is basically depth - normalized counts, whereas tpm is length - normalized ( and then normalized by the length - normalized values of the other genes ). if one has to choose between those two choices one typically chooses tpm for... | https://api.stackexchange.com |
the other answers here, describing oxygen toxicity are telling what can go wrong if you have too much oxygen, but they are not describing two important concepts that should appear with their descriptions. also, there is a basic safety issue with handling pressure tanks of high oxygen fraction. an important property of ... | https://api.stackexchange.com |
the air out of you ( like a tube of toothpaste ) is about 1. 3 atm. your diaphragm is not strong enough to overcome the squeezing and fill your lungs with air. divers overcome this problem by using a regulator ( specifically, a demand valve ), which allows the gas pressure at the outlet to be very near that of the ambi... | https://api.stackexchange.com |
ngspice is available for geda. gnucap is also available for geda. ltspice is free from linear technology. i thought that one of the other analog chip makers had a spice too but i can't remember who : ( i have been to a few talks on simulation given by physicists and ees who have done chip design. each of the talks seem... | https://api.stackexchange.com |
in fact, the idea of a plant nervous system is quite serious and constantly developing ; of course those are rather local, simple signal pathways rather than an " animalian " centralized global network, but they use similar mechanisms - - depolarisation waves, neurotransmitter - like compounds, specialized cells... her... | https://api.stackexchange.com |
i'll quote from $ \ ce { [ 1 ] } $ : the general requirements for an odorant are that it should be volatile, hydrophobic and have a molecular weight less than approximately 300 daltons. ohloff ( 1994 ) has stated that the largest known odorant is a labdane with a molecular weight of 296. the first two requirements make... | https://api.stackexchange.com |
> 300 da } $ " general requirement " provided above by turin & yoshii, a comparison of its estimated density to that of, e. g., labdane, indicates it's a much smaller molecule ( iodoform's three iodine atoms add a lot of mass without a lot of size, at least relative to carbon, hydrogen, and oxygen ) : i couldn't find l... | https://api.stackexchange.com |
). 2nd ed., marcel dekker, 2003. $ \ ce { [ 2 ] } $ : ohloff, g. scent and fragrances : the fascination of odors and their chemical perspectives. berlin, springer, 1994. $ \ ce { [ 3 ] } $ : wrobel d, wannagat u. sila perfumes. 2. silalinalool. chemischer informationsdienst. 13 ( 30 ), jul 27, 1982. $ \ ce { [ 4 ] } $ ... | https://api.stackexchange.com |
actually this is one of the main problems you have when analyzing scrna - seq data, and there is no established method for dealing with this. different ( dedicated ) algorithms deal with it in different ways, but mostly you rely on how good the error modelling of your software is ( a great read is the review by wagner,... | https://api.stackexchange.com |
there are several reasons for using the hamiltonian formalism : statistical physics. the standard thermal states weight of pure states is given according to $ $ \ text { prob } ( \ text { state } ) \ propto e ^ { - h ( \ text { state } ) / k _ bt } $ $ so you need to understand hamiltonians to do stat mech in real gene... | https://api.stackexchange.com |
algebra. | https://api.stackexchange.com |
if you are interested in conducting an analysis on sparse matrices, i would also consider davis's university of florida sparse matrix collection and the matrix market. | https://api.stackexchange.com |
first let's deal with a false assumption : similar to the way that the sum of a huge number of randomly selected 1's and - 1's would never stray far from 0. suppose we have a set of $ n $ random variables $ x _ i $, each independent and with equal probability of being either $ + 1 $ or $ - 1 $. define $ $ s = \ sum _ {... | https://api.stackexchange.com |
this can be arbitrarily large. another way of looking at this is that the more coins you flip, the less likely you are to be within a fixed range of breaking even. now let's apply this to the slightly more advanced case of independent phases of photons. suppose we have $ n $ independent photons with phases $ \ phi _ i ... | https://api.stackexchange.com |
_ j ). $ $ paralleling the computation above, we have $ $ \ langle i \ rangle = \ langle n \ rangle + 2 \ sum _ { i = 1 } ^ n \ sum _ { j = i + 1 } ^ n \ frac { 1 } { ( 2 \ pi ) ^ 2 } \ int _ 0 ^ { 2 \ pi } \! \! \ int _ 0 ^ { 2 \ pi } \ cos ( \ phi - \ phi') \ \ mathrm { d } \ phi \ \ mathrm { d } \ phi'= n + 0 = n. $... | https://api.stackexchange.com |
} ) ^ 2 ( 140 \ \ mathrm { w / m ^ 2 } ) ( 0. 02 \ \ mathrm { s } ) } { 3. 6 \ times10 ^ { - 19 } \ \ mathrm { j } } \ approx 2 \ times10 ^ 7. $ $ the fractional change in intensity from " frame to frame " or " pixel to pixel " in your vision would be something like $ 1 / \ sqrt { n } \ approx 0. 02 \ % $. even give or... | https://api.stackexchange.com |
i can not help but think : this is divide & conquer, plain and simple! m / r is not divide & conquer. it does not involve the repeated application of an algorithm to a smaller subset of the previous input. it's a pipeline ( a function specified as a composition of simpler functions ) where pipeline stages are alternati... | https://api.stackexchange.com |
what's the relationship between sigma and radius? i've read that sigma is equivalent to radius, i don't see how sigma is expressed in pixels. or is " radius " just a name for sigma, not related to pixels? there are three things at play here. the variance, ( $ \ sigma ^ 2 $ ), the radius, and the number of pixels. since... | https://api.stackexchange.com |
both $ x $ and $ y $. this means i have a grid resolution of $ \ frac { 10 - ( - 10 ) } { 100 } = 0. 2 $. but this is completely arbitrary. with those settings, i will get the probability density function image on the left. now, if i change the'variance ', ( really, the covariance ), such that $ \ boldsymbol { \ sigma ... | https://api.stackexchange.com |
back in the pleistoscene ( 1960s or earlier ), logic was implemented with bipolar transistors. even more specifically, they were npn because for some reasons i'm not going to get into, npn were faster. back then it made sense to someone that the positive supply voltage would be called vcc where the " c " stands for col... | https://api.stackexchange.com |
rigorous arguments are very similar to computer programming - - - you need to write a proof which can ( in principle ) ultimately be carried out in a formal system. this is not easy, and requires defining many data - structures ( definitions ), and writing many subroutines ( lemmas ), which you use again and again. the... | https://api.stackexchange.com |
the question really, since you don't know whether the planetary perturbations are big enough to lead to instability for 8 planets some big moons, plus sun. continuum statistical mechanics : what is a thermodynamic ensemble for a continum field? what is the continuum limit of a statistical distribution? what are the con... | https://api.stackexchange.com |
machinery are used. 3 ) what are examples that insisting on rigour delayed progress in physics. this has happened several times, unfortunately. statistical mechanics : the lack of rigorous proof of boltzmann ergodicity delayed the acceptance of the idea of statistical equilibrium. the rigorous arguments were faulty - -... | https://api.stackexchange.com |
progress in field theory was halted for a decade, until rigor was thrown out again in the 1970s. but a proper rigorous formulation of quantum fields is still missing. in addition to this, there are countless no - go theorems that delayed the discovery of interesting things : time cannot be an operator ( pauli ) : this ... | https://api.stackexchange.com |
##lies came directly from a physical observation ( the high rate of neutral pion decay to two photons ). clarifying how this happens through feynman diagrams, even though a naive argument says it is forbidden led to complete understanding of all anomalous terms in terms of topology. this in turn led to the development ... | https://api.stackexchange.com |
know what you're talking about ( since you have a hard time following the conventions ). this is improved by the internet, since the barriers to entry have fallen down dramatically, and there might be a way to merge rigorous and nonrigorous thinking today in ways that were not possible in earlier times. | https://api.stackexchange.com |
this is a reference resources question, masquerading as an answer, given the constraints of the site. the question hardly belongs here, and has been duplicated in the overflow cousin site. it might well be deleted. there have been schools and proceedings on the subject, integrability : from statistical systems to gauge... | https://api.stackexchange.com |
having my own 6 - year - old and having successfully explained this, here's my advice from experience : don't try to explain gravity as a mysterious force. it doesn't make sense to most adults ( sad, but true! talk to non - physicists about it and you'll see ), it won't make sense to a 6yo. the reason this won't work i... | https://api.stackexchange.com |
the first time, or the tenth, but pieces of it will stick. don't try to instill a grasp of the overall working model. if you can successfully give them some single, disconnected facts that they actually believe, putting them together will happen as they age and mature and get more exposure to this stuff. all this is as... | https://api.stackexchange.com |
as far as i know, no but the vcf. gz files are behind a http server that supports byte - range, so you can use tabix or any related api : $ tabix " " 22 : 17265182 - 17265182 " 22 17265182. a t 762. 04 pass ac = 1 ; af = 4. 78057e - 06 ; an = 209180 ; baseqranksum = - 4. 59400e + 00 ; clippingranksum = 2. 18000e + 00 ;... | https://api.stackexchange.com |
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