Update rocketpy/Function.py

Improved documentation

Co-authored-by: Giovani Hidalgo Ceotto <[email protected]>

Author: gautamsaiy

rocketpy/Function.py

@@ -2122,7 +2122,7 @@ def inverseFunction(self, lower=None, upper=None, datapoints=100):
         lower : float
             Lower limit of the new domain. Only required if the Function's source is a callable instead of a list of points.
         upper : float
-            Upper limit of the new domain.
+            Upper limit of the new domain. Only required if the Function's source is a callable instead of a list of points.
 
         Returns
         -------