This can lead to rounding errors when passing floating point numbers. For example, the value 39.99999999999 will be converted to 39 instead of 40. I suggest to use round() instead (which already converts to integer, so no subsequent typecast needed).
This behavior also occurs in other functions such as getQuadrupoleMatrixElement()
In getRadialMatrixElement(), the input parameters are converted to integer via a typecast:
https://github.com/nikolasibalic/ARC-Alkali-Rydberg-Calculator/blob/265fa0a9c06f95fa9225445aa87502c0a5f812f1/arc/alkali_atom_functions.py#L800-L805
This can lead to rounding errors when passing floating point numbers. For example, the value 39.99999999999 will be converted to 39 instead of 40. I suggest to use round() instead (which already converts to integer, so no subsequent typecast needed).
This behavior also occurs in other functions such as getQuadrupoleMatrixElement()