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User defined functions

It is possible to define numerical functions by formulas, using the command functdef :

- interpcom -> functdef ff(X,Y,Z)  X*X+Y*Y-sin(Z)

defines a function called ff with 3 variables. It is possible to use up to 10 variables. Their names need not to be X,Y,Z.. as in the above example. For instance we could use

- interpcom -> functdef ff(AB,CD,ZZ)  AB*AB+CD*CD-sin(ZZ)

It is then possible to use the function inside numerical expressions.

It is possible to use such functions into others :

- interpcom -> functdef G(A,B)  A+ff(B,A,-A*B)

The command listfunc gives the list of the user defined functions (cf. 11).

There is no command to destroy user defined numerical functions, but it is possible to give a new definition of a function (the old formula will then be erased in this case).