test_skymap_flux.py
2.08 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
#! /usr/bin/env python
# ==========================================================================
# This script tests the accuracy of the GSkyMap flux computation.
#
# --------------------------------------------------------------------------
#
# Copyright (C) 2015 Juergen Knoedlseder
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
#
# ==========================================================================
import math
import gammalib
# Set integration paramters
dr = 0.001
da = 0.1
nr = 1000
na = 3600
dr_rad = dr * gammalib.deg2rad
da_rad = da * gammalib.deg2rad
# Allocate GSkyMap
map = gammalib.GSkyMap("CAR", "GAL", 0.0, 0.0, -1.0, 1.0, 360, 180)
#map = gammalib.GSkyMap("GAL", 64, "RING")
# Loop over all pixels
for index in range(map.npix()):
# Set map pixel flux
map[index] = 1000000.0
# Get flux using flux() method
flux = map.flux(index)
# Get sky direction of pixel
dir = map.inx2dir(index)
#print(dir)
# Compute flux by integration
sum = 0.0
for ir in range(1,nr):
r = ir*dr
r_rad = r * gammalib.deg2rad
sum_az = 0.0
for ia in range(na):
a = ia*da
loc = dir.copy()
loc.rotate_deg(a,r)
if map.dir2inx(loc) == index:
sum_az += map(loc) * da_rad
sum += sum_az * math.sin(r_rad) * dr_rad
# Unset map pixel flux
map[index] = 0.0
# Print result
print("%15s flux()=%.5f integration=%.5f delta=%.2f%%" % \
(dir, flux, sum, (flux-sum)/sum*100.0))