How to add a new pump curve and assign it to the old pump

Hello.
I am trying to add a new pump curve (Q,H) and assign it to the old pump. but how can I do that

Hi,
To add a new curve use the EN_addcurve function then use EN_setcurve or EN_setcurvevalue to assign values to the new curve.
After you have added the curve use EN_setlinkvalue with EN_PUMP_HCURVE to assign the curve to the pump.
Please see the documentation here:
http://wateranalytics.org/EPANET/

Thank you very much. I appreciate your help