scientific-computing Questions

4

Solved

Is there a numerically stable way to compute softmax function below? I am getting values that becomes Nans in Neural network code. np.exp(x)/np.sum(np.exp(y))
Fountainhead asked 4/3, 2017 at 18:11

6

Solved

I have got a problem (with my RAM) here: it's not able to hold the data I want to plot. I do have sufficient HD space. Is there any solution to avoid that "shadowing" of my data-set? Concretely I ...
Exodus asked 2/5, 2011 at 7:25

6

Solved

is there a more efficient way to take an average of an array in prespecified bins? for example, i have an array of numbers and an array corresponding to bin start and end positions in that array, a...
Atheroma asked 28/5, 2011 at 17:43

4

Solved

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: ...
Mccahill asked 28/12, 2012 at 15:21

4

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 ...
Mangrove asked 29/11, 2010 at 21:15

4

Solved

I have a project written in C# where I need to do various linear algebraic operations on matrices (like LU-factorization). Since the program is mainly a prototype created to confirm a theory...
Estimate asked 17/9, 2009 at 8:36

5

Solved

Is there a way to set a maximum running time for AWS Batch jobs (or queues)? This is a standard setting in most batch managers, which avoids wasting resources when a job hangs for whatever reason. ...

1

For a Lattice Boltzmann simulation of a lid-driven cavity (CFD) I'm decomposing my cubic domain into (also cubic) 8 subdomains, which are computed independently by 8 ranks. Each MPI rank is produci...
Woolsack asked 9/6, 2014 at 15:22

4

Solved

I have two lists: 1 is a depth list and the other is a chlorophyll list, which correspond to each other. I want to average chlorophyll data every 0.5 m depth. chl = [0.4,0.1,0.04,0.05,0.4,0.2,0.6,...
Sutphin asked 15/4, 2018 at 16:54

3

Solved

I am using python for scientific applications. I run simulations with various parameters, my script outputs the data to an appropriate directory for that parameter set. Later I use that data. Howev...
Stinger asked 27/4, 2014 at 8:27

1

Solved

In BLAS there are routines like dscal scale a vector by a constant dinit initialize a vector with given value daxpy perform y = a*x + y and so on. But there are apparently no routines for vect...
Glaucous asked 7/2, 2018 at 14:41

3

Solved

I have a list of 3D points p stored in an ndarray with shape (N, 3). I want to compute the outer product for each 3d point with itself: N = int(1e4) p = np.random.random((N, 3)) result = np....
Goldplate asked 4/12, 2017 at 0:38

5

Solved

Is there a way to include git commit hashes inside a file everytime I commit? I can only find out how to do this during archiving but I haven't been able to find out how to do this for every commit...
Alben asked 17/5, 2010 at 22:1

3

Solved

I have about 500 HDF5 files each of about 1.5 GB. Each of the files has the same exact structure, which is 7 compound (int,double,double) datasets and variable number of samples. Now I want to co...
Volta asked 17/3, 2011 at 23:39

1

It seems whenever I run ARIMA.fit(), I always get a stdout from the kalman filter: ## -- End pasted text -- RUNNING THE L-BFGS-B CODE * * * Machine precision = 2.220D-16 N = 1 M = 12 This pro...
Grandnephew asked 7/8, 2015 at 18:29

10

Solved

I'm currently taking a math class in College called "Scientific Computing" and the professor told us that C is the most common language used for, well, scientific computing and am just wondering as...
Badgett asked 13/9, 2009 at 3:3

2

Solved

At the moment I am working with Spyder and doing my plotting with matplotlib. I have two monitors, one for development and another for (data) browsing and other stuff. Since I am doing some calcula...
Goldeneye asked 9/1, 2015 at 13:42

1

Solved

The upshot of the below is that I have an embarrassingly parallel for loop that I am trying to thread. There's a bit of rigamarole to explain the problem, but despite all the verbosity, I think thi...

4

Solved

For my current project in C++ / Qt I need a library (LGPL is preferred) which can calculate a spectrogram from a signal ( basically an array of doubles ). I already use Qwt for the GUI part. ...
Devin asked 25/1, 2010 at 16:15

8

Solved

Along with producing incorrect results, one of the worst fears in scientific programming is not being able to reproduce the results you've generated. What best practices help ensure your analysis i...
Adelaidaadelaide asked 29/4, 2010 at 1:7

7

C# seems to show some promise for scientific computing, but I found very little about one plotting 2D graphs, which is very important both for science student and scientists. Is there a reli...
Mcloughlin asked 15/2, 2009 at 5:28

4

Solved

I am new to python and learning by following Python "Scientific lecture notes Release 2013.1" tutorial. Please help me solve this Mandelbrot problem in the srcreenshot below (Pg 71). Please provide...
Sices asked 22/2, 2013 at 12:40

3

Solved

I have a (large) length-N array of k distinct functions, and a length-N array of abcissa. I want to evaluate the functions at the abcissa to return a length-N array of ordinates, and critically, I ...
Cageling asked 11/2, 2015 at 16:51

5

I'm working on a random walk simulation of particles moving in a lattice. For that reason I must create a massive amount of random numbers, about 10^12 and above. Currently I'm using the possibilit...
Algo asked 26/9, 2014 at 5:29

5

Solved

I am working on probabilistic models, and when doing inference on those models, the estimated probabilities can become very small. In order to avoid underflow, I am currently working in the log dom...
Scutch asked 17/2, 2012 at 23:6

© 2022 - 2024 — McMap. All rights reserved.