How to calculate planet’s Longitudinal speed ?

[Ram3k333]

Hello Sir, I’m working on a astrology software and I don’t know how to calculate **Planet’s Longitudinal Speed in degrees/day.
I tried pyswisseph for speed but it’s not precise
We can calculate speed using swisseph here’s a method —>
Swisseph.cal_ut(jd,planet,speed_flag)[0][3] Here jd = Julian Date, planet = planet name, flag is speed flag. So please help me how can I calculate longitudinal speed in degrees/day.