# Defining the analytic integral of a TF1

Dear all,

although I’m defining some complicate fitting function, I know the analytic integral (and the derivative) and would like to know if it is possible to define a TF1 object which can be configured to use this integral (or the derivative) instead of calculating it numerically.

Thanks,
Diego

Hi Diego,

You may want to post this question in the Math and Stats forum.

Cheers,
Philippe.

Hi Diego

At the moment this is not possible, when you call TF1:integral or Derivative a numeric computation is done. You need then to create separate TF1 objects for this. We could eventually implement this functionality in the future

ciao

lorenzo