Help with functions interpolation number generation

I have a given function gen_cdf_weibull that outputs a 100x2 array but I'm trying to define this array as weibull_cdf and i dont know how. I have coded to generate a random number y and interpolate for it's corrosponding x value from weibull_cdf but it obviously doesnt work as it's not defined. here's what i've got so far

gen_CDF_Weibull

y=rand() x= interp1(CDF_Weibull(:,2), CDF_Weibull(:,1), y)

(gen_cdf_weibull is saved as a seperate script) I want to run a forloop 8766 times of this number generation and interpolation but not sure how to do that either as I've never managed to get my head around loops!!! thnx in advance for any help given