MATLAB: How to fix a randomly generated sample in Matlab after making some changes to the code

MATLABno replacementrandpermsampling

I need to have the same sample (same data points) that was generated from a large set of data in order to make some comparisons as I vary some conditions or parameters. However, the sample changes after each Matlab run. My current sampling is based on the use of "randperm" or sampling without replacement.

Any help would e greatly appreciated. Thanks.

Best Answer

You can use rng to control the random number generation, for example (from that link):

s = rng;
x = rand(1,5)
x =
    0.8147    0.9058    0.1270    0.9134    0.6324
rng(s);
y = rand(1,5)
y =
    0.8147    0.9058    0.1270    0.9134    0.6324

You can also use the seed option to reset the random numbers to a known starting point:

rng(N)

Related Solutions

MATLAB: How to save the RNG state for later reproducibility

Of course you can find such details in the documentation: doc rng

state = rng;
x = rand(1,5)
x =
  0.8147    0.9058    0.1270    0.9134    0.6324
rng(state);
y = rand(1,5)
y =
  0.8147    0.9058    0.1270    0.9134    0.6324

Storing the state in a text file is not trivial, because it is a struct. Prefer a MAT file using save and load:

File = fullfile(tempdir, 'RNGState.mat');
save(File, 'state');
...
Data  = load(File);
state = Data.state;

MATLAB: If a = 3*3 Matrix then how to index row 1,2,3 & column 1,3

A(:, [1,3])

Best Answer

Related Solutions

MATLAB: How to save the RNG state for later reproducibility

MATLAB: If a = 3*3 Matrix then how to index row 1,2,3 & column 1,3

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