convertCategorical

A code to convert categorical vectors to double vectors or numerical arrays

This code is to convert a categorical vector to a double or numeric vector using the grp2idx function. This is because the labels for LSTM networks and the Neural Network toolbox of MATLAB should be categorical, but you cannot compare two categorical variables or subtract them to find the RMSE, etc.
% An example demonstrating the idea behind this code:
% y = [0,1,3,4,6,0,1]
% ycat = categorical(y)
% [g,gN] = grp2idx(ycat)
% gN(g)
% ydouble = str2num(cell2mat(gN(g)))