Write a matlab function b = ubitname hw6 p3(a, p) that accepts a matrix a and returns the rank-p matrix b that is the best approximation to a in the 2-norm. if the requested rank p is larger than rank(a) simply return matrix a. you may use the matlab functions svd, diag, rank, zeros, and size to produce the result. you may not use any other built-in matlab function. note that commands like if, for, etc are not considered matlab functions. note: you may consider that any singular value below 10−14 as zero. upload your code to ublearns.