Pls help me about finding 2 singular value of a fix size matrix (2*360) very very fast !!!!

hi i have a fix size matrix 2*360 and want to find its 2 singular value of it n times in aloop . i used s=svd(X) and s=svd(X,0), but it is very slow for me . pls help me !!! i need very very fast or full optimized version of svd fo my fix size matrix to get me the same result of s=svd(X), i just need 2 singular value of my matrix x and do not want matrix U , V at all .

i guess matlab svd use many extra step that consumes time and can be ommitted for a fix size matrix 2*360 . but i do not know how to ommit them to optimize matlab svd for my fix size matrix 2*360 . beside i do not have svd source in matlab . it is hidden .

is there any way to get a very very fast finding svd for my algorithm !!! thank u in advance !!!