Use fmod rather than np.mod: it is slightly faster

bilby/gw/utils.py

 from __future__ import division
 import os
 import json
+from math import fmod
 
 import numpy as np
 from scipy.interpolate import interp1d
@@ -87,7 +88,7 @@ def time_delay_geocentric(detector1, detector2, ra, dec, time):
     float: Time delay between the two detectors in the geocentric frame
 
     """
-    gmst = np.mod(lal.GreenwichMeanSiderealTime(time), 2 * np.pi)
+    gmst = fmod(lal.GreenwichMeanSiderealTime(time), 2 * np.pi)
     theta, phi = ra_dec_to_theta_phi(ra, dec, gmst)
     omega = np.array([np.sin(theta) * np.cos(phi), np.sin(theta) * np.sin(phi), np.cos(theta)])
     delta_d = detector2 - detector1
@@ -120,7 +121,7 @@ def get_polarization_tensor(ra, dec, time, psi, mode):
     array_like: A 3x3 representation of the polarization_tensor for the specified mode.
 
     """
-    gmst = np.mod(lal.GreenwichMeanSiderealTime(time), 2 * np.pi)
+    gmst = fmod(lal.GreenwichMeanSiderealTime(time), 2 * np.pi)
     theta, phi = ra_dec_to_theta_phi(ra, dec, gmst)
     u = np.array([np.cos(phi) * np.cos(theta), np.cos(theta) * np.sin(phi), -np.sin(theta)])
     v = np.array([-np.sin(phi), np.cos(phi), 0])