Getting largest indices of array less than or equal to an array of numbers

[schniefen]

I realize that what I want is not quite what I have said, so I'm restating it:

Suppose

y_i=np.linspace(np.zeros(d),np.ones(d),m+1)

and the values between 0 and 1 (the first and last row) are changed in a later statement of the code. Then, for

y=np.random.uniform(0,1,d)

I'd like to find the index of the number in the i'th column of y_i greater than or equal to the i'th entry of y.