MFIT /STEP

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MFIT /STEP

              [SIC\]MFIT Y=f(X,&a,...) /STEP A2 B2 ...

        A2  B2  ... are used to pass the unity vectors (steps) for the iteration
        on parameters &A &B (defaulted to 0.25). Poor choice  of  initial  steps
        may  lead  to  non convergence. Too small steps will not help converging
        when one starts too far from the solution. Too large steps may  lead  to
        incorrect  evaluation  of the parameter errors. The optimal step for the
        determination of the errors is about the error bar, so that all  parame-
        ters become dimensionless.