# Wilcoxon two-sample test approximated by z-statistic [duplicate]

I have two long vectors (both of the same size=12000 and each of them contains variance values). I want to perform Wilcoxon test to test if the variances in the first vector are different than the second vector. As the vectors are of long size, I had to use the normal distribution approximation. Simply, I used matlab's ranksum function which calculates the test p-value.