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#!/usr/bin/env python
# import libraries
import time
import numpy as np
import sys
# define the number of stars that should be generated
nos = int(sys.argv[1])
# define some arrays for storing the values
arr_stars = np.zeros((int(nos), 3))
arr_saved_stars = np.zeros((int(nos), 3))
# define various paths
path = "data/2e7.csv"
save_path = "stars/" + sys.argv[2] + ".csv"
# star13 -> 586 stars
# define the random-value range [rho_min; rho_max]
rand_min = 0
rand_max = 1477.1586582000994
# define the range (size) of the galaxy
range_min = -1e7
range_max = 1e7
# main function
def main():
# define the variables for storing the amount of stars kept or kicked away
stars_kept = 0
stars_kicked = 0
i = 0
# start the timer
start = time.time()
# open the rho file
with open(path) as data:
# read out the lines from the rho file
rho_file = data.readlines()
# for every star...
# for i in range(0, nos):
while(stars_kept < nos):
# generate the random star-coordinates
x = np.random.uniform(range_min, range_max, size=1)
y = np.random.uniform(range_min, range_max, size=1)
z = np.random.uniform(range_min, range_max, size=1)
# calculate the distance of the star to the center of the galaxy
r = np.sqrt(pow(x, 2) + pow(y, 2) + pow(z, 2))
# print(round(int(r), 0))
# generate a random value in the range [rand_min; rand_max]
a = np.random.uniform(rand_min, rand_max, size=1)
# print(a)
# read out the corresponding rho value from the lookuptable (rho-file)
b = float(rho_file[round(int(r), 0)].split(", ")[1].strip("\n"))
# if the random value is smaller than the corresponding rho value
if(a < b):
# add the coordinate to arr_saved_stars
arr_saved_stars[stars_kept][0] = x
arr_saved_stars[stars_kept][1] = y
arr_saved_stars[stars_kept][2] = z
# increment the star_kept counter
stars_kept += 1
print(stars_kept)
else:
# increment the star_kicked counter
stars_kicked += 1
# increment i
i = i + 1
print("")
end = time.time()
whole_time = end - start
out = ">> Finished generating stars in " + str(whole_time) + " seconds\n"
print(out)
# write the star coordinates to a file
start_write_file = time.time()
print(">> Writing the star-data to " + save_path)
with open(save_path, "a") as stars_data:
for i in range(0, nos):
x = arr_saved_stars[i][0]
y = arr_saved_stars[i][1]
z = arr_saved_stars[i][2]
stars_data.write(str(x) + ", " + str(y) + ", " + str(z) + "\n")
end_write_file = time.time()
time_write_file = end_write_file - start_write_file
out = ">> Finished writing star-data to " + save_path + " in " + str(round(time_write_file, 4)) + " seconds\n"
print(out)
time_all = whole_time + time_write_file
time_min = round(time_all / 60, 1)
# print some stats
print("")
print("{:<20}{:<20}".format("Time (complete)", str(round(time_all, 4)) + " seconds"))
print("{:-<40}".format(""))
print("{:<20}{:<20}".format("Number of Stars", str(nos)))
print("{:<20}{:<20}".format("Stars Kicked:", str(stars_kicked)))
print("{:<20}{:<20}".format("Percent: ", str( nos / stars_kicked * 100 ) + "%"))
if __name__ == "__main__":
main()
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