Replace sas_temper_engine.py - changed some comments in the code, but no code was changed

# perform the traditional estimation of the uncertainties in the

# fitting parameters by looking at the partial derivatives using the

# approach that is used in Paul Kienzle's "bump", as is noted below.    

# approach that is used in Paul Kienzle's "bumps", as is noted below.

# https://github.com/bumps/bumps/blob/master/LICENSE.txt 

def est_uncerts(d, f, modconf, best_model):

    # this is our ugly way of getting at this matrix of derivatives

    loc = modelconfig.ModelConfig(f.name,f.category,f.params,f.sq)

    # print(J)

    # this is the singlular value decomposition of J

    # see https://github.com/bumps/bumps/blob/master/bumps/lsqerror.py lines 237-239

    # see https://github.com/bumps/bumps/blob/master/bumps/lsqerror.py 

    # bumps is by Paul Kienzle, who works at NIST's NCNR

    # https://github.com/bumps/bumps/blob/master/LICENSE.txt

    # The tolerance shown cuts down on singlular values

    # bumps as a whole may not use this directly.  have to give it a try, though

    # bumps as a whole may not use this directly.

    U, S, V = np.linalg.svd(J, 0)

    tol = 1e-8

    S[S <= tol] = tol