scientific-computing

Motivation: I have a multidimensional integral, which for completeness I have reproduced below. It comes from the computation of the second virial coefficient when there is significant anisotropy: Here W is a function of all the variables. It is a known function, one which I can define a python function for. Programming Question: How do I get scipy to integrate this expression? I was thinking of chaining two triple quads ( scipy.integrate.tplquad ) together, but I'm worried about performance and accuracy. Is there a higher dimensional integrator in scipy , one that can handle an arbitrary

I have two variables (x and y) that have a somewhat sigmoidal relationship with each other, and I need to find some sort of prediction equation that will enable me to predict the value of y, given any value of x. My prediction equation needs to show the somewhat sigmoidal relationship between the two variables. Therefore, I cannot settle for a linear regression equation that produces a line. I need to see the gradual, curvilinear change in slope that occurs at both the right and left of the graph of the two variables. I started using numpy.polyfit after googling curvilinear regression and

I just took my first baby step today into real scientific computing today when I was shown a data set where the smallest file is 48000 fields by 1600 rows (haplotypes for several people, for chromosome 22). And this is considered tiny. I write Python, so I've spent the last few hours reading about HDF5, and Numpy, and PyTable, but I still feel like I'm not really grokking what a terabyte-sized data set actually means for me as a programmer. For example, someone pointed out that with larger data sets, it becomes impossible to read the whole thing into memory, not because the machine has

I often hear people complain how expensive MATLAB licenses are. Then I wonder why they don't just use Octave or R . But is the latter right? Can you use R to replace MATLAB? Shane Can you use R to replace MATLAB? Yes. I used MATLAB for years but switched primarily to R in the last 3 years. At this point, they have much more in common than not. It partially depends on your field and use-case. And as Spencer Graves said previously , it also depends on which "church you happen to frequent". It's best if you look at the MATLAB toolkit vs. CRAN for a specific task before you decide. A similar

Let's say I have class that contains a lot of fields and I want to make initializer that work for all fields so that I don't need to write an initializer for each of them. class Foo(): def __init__(n): self.n = n self.x = None self.m = None self.v = None but method def init_x(self, x): # initialize or erase x to zeros x = np.zeros(self.n) doesn't work because x= loses reference to x . But @staticmethod def get_x(x, i): return x[i] @staticmethod def set_x(x, i): x[i] = val works. What could possibly make my init_x to work? I want to set the fields to None initially cuz there are other things

I am now trying to solve an exponential equation in MATLAB as a part of my assignment. It is easy to see that the equation exp(-t)+t*exp(-t)-n=0 would have two solutions, one greater than zero and one smaller. However, using just the solve function, MATLAB returns something called lambertw function and it can only eval() to the solution below zero, which happens not to be the one I want for the answer. Could anyone help me here? Thanks in advance for all the answers and comments! p.s. As an alternative, I am thinking about using Newton-Raphson method to solve it, but I wonder how is the speed

I have downloaded PyDsTool for Windows. And I believe I have pointed python in the correct location. But I get the following error from PyDSTool import * Traceback (most recent call last): File "<ipython-input-1-7b811358a37e>", line 1, in <module> from PyDSTool import * File "C:\Anaconda\lib\site-packages\pydstool-0.88.140328-py2.7.egg\PyDSTool\__init__.py", line 85, in <module> from .Events import * File "C:\Anaconda\lib\site-packages\pydstool-0.88.140328-py2.7.egg\PyDSTool\Events.py", line 13, in <module> from .Variable import * File "C:\Anaconda\lib\site-packages\pydstool-0.88.140328-py2.7