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# This file is part of the Astrometry.net suite.
# Licensed under a 3-clause BSD style license - see LICENSE
from __future__ import print_function
import matplotlib
if __name__ == '__main__':
matplotlib.use('Agg')
import unittest
try:
import pyfits
except ImportError:
try:
from astropy.io import fits as pyfits
except ImportError:
raise ImportError("Cannot import either pyfits or astropy.io.fits")
from astrometry.util.fits import *
from astrometry.plot.plotstuff import *
import numpy as np
import pylab as plt
from math import pi,sqrt
class TestPlotstuff2(unittest.TestCase):
def testSubpixelShift(self):
W,H = 100,100
cx,cy = 34.2, 56.7
X,Y = np.meshgrid(np.arange(W), np.arange(H))
S = 2.
G = 1./(2.*pi*S**2) * np.exp(-((X-cx)**2+(Y-cy)**2)/(2.*S**2))
#G /= G.max()
print(G.sum())
print(np.sum(G*X), np.sum(G*Y))
imfn = 'test-plotstuff-2.fits'
pyfits.writeto(imfn, G, clobber=True)
wcs = anwcs_create_box(33.5, 10.4, 1., W, H)
anwcs_rotate_wcs(wcs, 25.)
wcsfn = 'test-plotstuff-2.wcs'
anwcs_write(wcs, wcsfn)
plot = Plotstuff()
plot.outformat = PLOTSTUFF_FORMAT_PNG
plot.size = (W,H)
plot.wcs_file = wcsfn
plot.color = 'black'
plot.plot('fill')
im = plot.image
im.image_low = 0
im.image_high = G.max()
plot_image_set_wcs(im, wcsfn, 0)
plot_image_set_filename(im, imfn)
plot.plot('image')
plotfn = 'test-plotstuff-2.png'
plot.write(plotfn)
I = plt.imread(plotfn)
I = I[:,:,0]
sx,sy = (I*X).sum()/I.sum(), (I*Y).sum()/I.sum()
print(sx,sy)
ex,ey = cx,cy
self.assertTrue(abs(sx-ex) < 0.1)
self.assertTrue(abs(sy-ey)< 0.1)
# Shift the plot's WCS CRPIX.
dx = 0.25
dy = 0.3
sip = anwcs_get_sip(wcs)
tan = sip.wcstan
plotstuff_set_wcs(plot.pargs, wcs)
xy = plot.xy
plot_xy_set_wcs_filename(xy, wcsfn)
plot.marker = 'crosshair'
# Move the plot WCS origin
for step in range(16):
if step < 8:
tan.set_crpix(tan.crpix[0]+dx, tan.crpix[1])
ex += dx
else:
tan.set_crpix(tan.crpix[0], tan.crpix[1]+dy)
ey += dy
#anwcs_print_stdout(wcs)
plot.color = 'black'
plot.plot('fill')
plot.plot('image')
plotfn = 'test-plotstuff-2b%i.png' % step
plot.write(plotfn)
#anwcs_write(plot.pargs.wcs, 'test-plotstuff-2b.wcs')
I = plt.imread(plotfn)
I = I[:,:,0]
sx,sy = (I*X).sum()/I.sum(), (I*Y).sum()/I.sum()
print(sx,sy)
print(ex,ey)
self.assertTrue(abs(sx-ex) < 0.1)
self.assertTrue(abs(sy-ey) < 0.1)
plot.color = 'red'
plot_xy_clear_list(xy)
# don't plot at sx,sy / ex,ey -- original image coords
# are unchanged.
plot_xy_vals(xy, cx+1, cy+1)
plot.plot('xy')
plotfn = 'test-plotstuff-2c%i.png' % step
plot.write(plotfn)
# visual check that plot xy symbols match source centroid -- yes
# Scan image WCS in RA,Dec; check that recovered source position
# through plot WCS matches.
# reset...
plot.wcs_file = wcsfn
plotwcs = anwcs_open(wcsfn, 0)
wcs = anwcs_open(wcsfn, 0)
im.wcs = wcs
sip = anwcs_get_sip(wcs)
tan = sip.wcstan
ddec = 1.2 * 1./W
ok,era,edec = anwcs_pixelxy2radec(wcs, cx, cy)
print(era,edec)
for step in range(16):
tan.set_crval(tan.crval[0], tan.crval[1] + ddec)
edec += ddec
plot.color = 'black'
plot.plot('fill')
plot.plot('image')
plotfn = 'test-plotstuff-2d%i.png' % step
plot.write(plotfn)
I = plt.imread(plotfn)
I = I[:,:,0]
sx,sy = (I*X).sum()/I.sum(), (I*Y).sum()/I.sum()
#print sx,sy
ok,ra,dec = anwcs_pixelxy2radec(plotwcs, sx, sy)
#print era,edec
#print ra,dec
print('dRA,dDec', ra-era, dec-edec)
self.assertTrue(abs(ra-era) < 1e-4)
self.assertTrue(abs(dec-edec) < 1e-4)
if __name__ == '__main__':
unittest.main()
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