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/*
# This file is part of the Astrometry.net suite.
# Licensed under a 3-clause BSD style license - see LICENSE
*/
/*
Write Matlab figures to demonstrate the correctness of the Healpix code.
*/
#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include "healpix.h"
#include "starutil.h"
#include "mathutil.h"
#define OPTIONS "hN:nM:F:rRe"
void print_help(char* progname) {
printf("usage:\n\n"
"%s\n"
" [-N <nside>] (default 1)\n"
" [-n]: draw lines to show neighbours\n"
" [-M <marker-size>]: change the size of the circles on the endpoints of the neighbour lines.\n"
" [-F <font-size>]\n"
" [-r]: show RING index\n"
" [-R]: show decomposed RING index (ring number + longitude index)\n"
" [-e]: show NESTED index\n"
"\n", progname);
}
enum modes {
MODE_XY,
MODE_XY_D,
MODE_RING,
MODE_RING_D,
MODE_NESTED
};
int main(int argc, char** args) {
int c;
int Nside = 1;
int HP, hp;
int i;
double* radecs;
double markersize = 20.0;
double fontsize = 10.0;
anbool do_neighbours = FALSE;
int mode = MODE_XY;
while ((c = getopt(argc, args, OPTIONS)) != -1) {
switch (c) {
case '?':
case 'h':
print_help(args[0]);
exit(0);
case 'N':
Nside = atoi(optarg);
break;
case 'n':
do_neighbours = TRUE;
break;
case 'M':
markersize = atof(optarg);
break;
case 'F':
fontsize = atof(optarg);
break;
case 'r':
mode = MODE_RING;
break;
case 'R':
mode = MODE_RING_D;
break;
case 'e':
mode = MODE_NESTED;
break;
}
}
HP = 12 * Nside * Nside;
printf("Nside=%i;\n", Nside);
radecs = malloc(HP * 2 * sizeof(double));
for (hp=0; hp<HP; hp++) {
double xyz[3];
double ra, dec;
healpix_to_xyzarr(hp, Nside, 0.5, 0.5, xyz);
xyzarr2radec(xyz, &ra, &dec);
radecs[2*hp] = ra;
radecs[2*hp+1] = dec;
}
printf("figure(1);\n");
printf("clf;\n");
printf("xmargin=0.5; ymargin=0.1;\n");
printf("axis([0-xmargin, 2*pi+xmargin, -pi/2-ymargin, pi/2+ymargin]);\n");
printf("texts=[];\n");
printf("lines=[];\n");
// draw the large-healpix boundaries.
for (hp=0; hp<12; hp++) {
double xyz[3];
double crd[6*2];
double xy[] = { 0.0,0.001, 0.0,1.0, 0.999,1.0,
1.0,0.999, 1.0,0.0, 0.001,0.0 };
for (i=0; i<6; i++) {
healpix_to_xyzarr(hp, 1, xy[i*2], xy[i*2+1], xyz);
xyzarr2radec(xyz, crd+i*2+0, crd+i*2+1);
}
printf("xy=[");
for (i=0; i<7; i++)
printf("%g,%g;", crd[(i%6)*2+0], crd[(i%6)*2+1]);
printf("];\n");
printf("[la, lb] = wrapline(xy(:,1),xy(:,2));\n");
printf("set(la, 'Color', 'b');\n");
printf("set(lb, 'Color', 'b');\n");
}
if (do_neighbours) {
for (hp=0; hp<HP; hp++) {
uint neigh[8];
uint nn;
nn = healpix_get_neighbours(hp, neigh, Nside);
for (i=0; i<nn; i++) {
printf("[la,lb]=wrapline([%g,%g],[%g,%g]);\n",
radecs[2*hp], radecs[2*neigh[i]],
radecs[2*hp+1], radecs[2*neigh[i]+1]);
printf("set([la,lb], "
"'Color', [0.5,0.5,0.5], "
"'Marker', 'o', "
"'MarkerEdgeColor', 'k', "
//"'MarkerFaceColor', 'none', "
"'MarkerFaceColor', 'white', "
"'MarkerSize', %g);\n", markersize);
printf("set(lb, 'LineStyle', '--');\n");
}
}
}
for (hp=0; hp<HP; hp++) {
printf("texts(%i)=text(%g, %g, '",
hp+1, radecs[2*hp], radecs[2*hp+1]);
switch (mode) {
case MODE_XY:
printf("%i", hp);
break;
case MODE_XY_D:
{
uint bighp, x, y;
healpix_decompose_xy(hp, &bighp, &x, &y, Nside);
printf("%i,%i,%i", bighp, x, y);
}
break;
case MODE_RING:
printf("%i", healpix_xy_to_ring(hp, Nside));
break;
case MODE_RING_D:
{
uint ring;
uint ringnum, longind;
ring = healpix_xy_to_ring(hp, Nside);
healpix_decompose_ring(ring, Nside, &ringnum, &longind);
printf("%i,%i", ringnum, longind);
}
break;
case MODE_NESTED:
printf("%i", healpix_xy_to_nested(hp, Nside));
break;
}
printf("', 'HorizontalAlignment', 'center', 'FontSize', %g);\n", fontsize);
}
// Verify decompose / compose RING.
for (hp=0; hp<HP; hp++) {
uint ring, longind;
int hp2;
healpix_decompose_ring(hp, Nside, &ring, &longind);
hp2 = healpix_compose_ring(ring, longind, Nside);
if (hp2 != hp) {
fprintf(stderr, "Error: %i -> ring %i, longind %i -> %i.\n",
hp, ring, longind, hp2);
}
}
// Verify XY -> RING -> XY
for (hp=0; hp<HP; hp++) {
int ring, hp2;
ring = healpix_xy_to_ring(hp, Nside);
hp2 = healpix_ring_to_xy(ring, Nside);
if (hp2 != hp) {
uint bighp, x, y;
uint bighp2, x2, y2;
uint ringind, longind;
healpix_decompose_xy(hp, &bighp, &x, &y, Nside);
healpix_decompose_xy(hp2, &bighp2, &x2, &y2, Nside);
healpix_decompose_ring(ring, Nside, &ringind, &longind);
fprintf(stderr, "Error: hp %i (bighp %i, x %i, y %i) -> ring %i (ring %i, long %i) -> hp %i (bighp %i, x %i, y %i).\n",
hp, bighp, x, y, ring, ringind, longind, hp2, bighp2, x2, y2);
}
}
free(radecs);
return 0;
}
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