pythonpython-3.xtypesscipyastronomy

Converting Betwixt (Between) String to Integer Datatype


I am trying to convert the distance of Jupiter which is in AU (Astronomical Unit) to Lightyears, I am using preexisting modules which means you have no preference over the data types and i am having the following error.

I am using the modules Skyfield (Skyfield.api to be specific) and Scipy My code:

from scipy import constants
from skyfield.api import load
planets = load('de421.bsp')
earth, jupiter = planets['earth'], planets['JUPITER BARYCENTER']
ts = load.timescale()
t = ts.now()
astrometric = earth.at(t).observe(jupiter)
radec=astrometric.radec()

# int(constants.astronomical_unit / constants.light_year ) * int(str(radec[2])

# Since the above line is not working i tried this:

int(constants.astronomical_unit / constants.light_year ) * int(str(radec[2]).replace("au", "").strip())








Error:

int(constants.light_year / constants.astronomical_unit) * int(str(radec[2]).replace("au", "")) ValueError: invalid literal for int() with base 10: '4.63954'

I at first thought the whitespace might be the reason but even when i applied the strip() function the error persists still

my Python version is Python 3.9.12


Solution

  • Try using int(radec[2].au) instead of int(str(radec[2])) so it becomes:

    int(constants.light_year / constants.astronomical_unit) * int(radec[2].au))
    

    If you print it you get 252964.

    Note: You should consider making all the calculations on floats and at the end, convert the answer to int:

    print(int(float(constants.light_year / constants.astronomical_unit) * float(radec[2].au)))
    

    Which gives 293505.