[Physics Module Sample Coordsys Python] #demo #sample #math

0Readme.md

coordsys.py

It is a simple module (developed for illustrative purposes) with functions for converting between radians and degrees and also between spherical and cartesian coordinates)

Shiva, 2014

coordsys.py

from pylab import *
def rad2dms(q):
	'''
	rad2dms : convert an angle in radian to a deg min sec tuple
	Usage: d,m,s=rad2dms(angle)
	'''
	qd=q*180/pi
	d=int(qd)
	qm=(qd - d)*60
	m=int(qm)
	s=(qm - m)*60
	return (d,m,s)
def dms2rad(q):
	'''
	dms2rad : convert a tuple containing deg, min, sec values to rad
	Usage: dms2rad((d,m,s))
	'''
	d,m,s=q
	return (pi/180.0)*(d+m/60.0+s/3600.0)
	
def CART(r,q,phi):
    '''
    cart::convert r,theta(q), phi(ph) to x,y,z
    NB: q is the angle of elevation from the x-y plane
    Usage: x,y,z=coordsys.CART(r,q,phi)
    EX 1: x,y,z=coordsys.CART(1,0,pi/4)
    '''
    rcst=r*cos(q)
    x=rcst*cos(phi);y=rcst*sin(phi);z=r*sin(q)
    return x,y,z

def POLAR(x,y,z):
	'''
	polar::convert x,y,z to r,q,phi
	NB: q is the angle of elevation from the x-y plane
	Usage: r,q,phi=coordsys.POLAR(x,y,z)
	EX 1: r,q,phi = coordsys.POLAR(0,0,4)	
	'''
	rho = sqrt(x**2+y**2); r = sqrt(rho**2+z**2)
	phi = arctan2(y,x)
	if phi < 0: phi = phi + 2*pi
	q = arctan2(z,rho)
	return r, q, phi