Cannot use 'histogram' to compute entropy
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I'd like to compute the entropy of various vectors. I was going to use something like:
X = randn(1,100);
h1 = histogram(X, 'Normalization', 'Probability');
probabilities = h1.Values;
entropy = -sum(probabilities .* log2(probabilities ))
The second command however gives the error:
Undefined function 'c:\Program Files\MATLAB\R2019b\toolbox\matlab\specgraph\histogram.m' for input arguments of type 'double'.
But surely that's exactly what the standard Matlab function 'histogram' expects?! Doing a
which is the newest file (by modified date) from several of that name that (sadly) exist in my Matlab folder. I believe this should be the standard Matlab function 'histogram'.
If on the other hand in the above example I use 'hist' instead of 'histogram', I get the scalar value for entropy that I expect. However, I know 'hist' is not recommended, not least because with it one cannot specify the normalization type.
So, my question is: is using 'hist' for computing probabilities ok, or should I try something else to be able to use 'histogram' instead?