Random button arrays

im trying to create a ‘random’ buttom to randomise the length and the values of 6 envelope arrays…i.e

~envstring = Array.fill(~Envs);
~envstring[~env1] = "Env.new([0,10,0],[0.147,20],[-10,1.5])";
~envstring[~env2] = "Env([5,7,3,9,2,7,3,8],[1,4,7,1,9,3,7],[1/4,1/2,2])";
~envstring[~env3]= "Env([1,5,2,7,3,8,4,5],[1,2,8,5,9,3,7])";
~envstring[~env4] = "Env([9,5,3,8,5,7],[1,6,3,5,2,7],[9,4,7,3,8,2])";
~envstring[~env5]  = "Env([5,7,2,5,3,8],[9,4,7,3,8,2])";
~envstring[~env6] = "Env([7,3,8,3,6,2],[1,4,2,6,8,4])";

any tips welcome