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Minuit Strategy.

At many places in the analysis of the user function, Minuit must decide whether to be ``safe'' and waste a few function calls in order to know where it is, or to be ``fast'' and attempt to get the requested results with the fewest possible calls at a certain risk of not obtaining the precision desired by the user. In order to allow the user to influence these decisions, there is an internal Minuit parameter ISTRAT which can be set by the user through the command SET STRategy. In the current release, this parameter can take on three integer values (0, 1, 2), and the default value is 1. Value 0 indicates to Minuit that it should economize function calls; it is intended for cases where there are many variable parameters and/or the function takes a long time to calculate and/or the user is not interested in very precise values for parameter errors. On the other hand, the value 2 indicates that Minuit is allowed to waste function calls in order to be sure that all values are precise; it is intended for cases where the function is evaluated in a very short time and/or where the parameter errors must be calculated reliably


Janne Saarela
Mon Apr 3 15:36:46 METDST 1995