/* axtype.c Copyright (c) Kapteyn Laboratorium Groningen 1990 All Rights Reserved. #> axtype.dc2 Function: AXTYPE Purpose: The function axtype returns the type of axis, the natural units, secondary units and the projection type. Category: PHYSICAL COORDINATES File: axtype.c Author: K.G. Begeman Use: INTEGER AXTYPE( CTYPE, Input CHARACTER*(*) CUNIT, Output CHARACTER*(*) DUNIT, Output CHARACTER*(*) SKYSYS, Output INTEGER PROSYS, Output INTEGER VELSYS ) Output INTEGER AXTYPE Returns: 0: unknown type of axis. 1: spatial axis longitude. 2: spatial axis latitude. 3: spectral axis frequency. 4: spectral axis velocity. 5: spectral axis wavelength. 6: spectral axis inverse wavelength. 7: spectral axis log(wavelength). 8: time axis. 9: polarisation axis. 10: parameter axis. 11: sample axis of iras data 12: tick axis of iras data 13: detector axis of iras data 14: snip axis of iras data CUNIT Natural axis units. DUNIT Secondary axis units. SKYSYS If AXTYPE equals 1 or 2, the sky system id: 1 = equatorial 2 = galactic 3 = ecliptic 4 = supergalactic PROSYS if AXTYPE equals 1 or 2, the sky projection system id: 1 = AITOFF equal area 2 = equivalent cylindrical 3 = flat 4 = gnomonic 5 = orthographic 6 = rectangular 7 = global sinusoidal 8 = north celestial pole (WSRT) 9 = stereographic 10 = mercator projection VELSYS If AXTYPE equals 3 the velocity system id: 1 = optical 2 = radio If AXTYPE equals 4 VELSYS = 2. Updates: Dec 11, 1989 : KGB, document created. Aug 28, 1991 : PRR, add IRDS axis types (SAMPLE etc.) Sep 24, 1999 : VOG, allow unknown axis names to be of parameter type. #< Fortran to C interface: @ integer function axtype( character , @ character , @ character , @ integer , @ integer , @ integer ) */ #include "stdio.h" /* */ #include "ctype.h" /* */ #include "string.h" /* */ #include "gipsyc.h" /* GIPSY symbols and definitions */ #define MAXBUFLEN 80 /* maximum length of axis name */ typedef struct { char *ctype; char *cunit; char *dunit; } c_struct; static c_struct NAMES[] = { { "RA" , "DEGREE" , "" }, /* Equatorial, right ascension */ { "DEC" , "DEGREE" , "" }, /* Equatorial, declination */ { "GLON" , "DEGREE" , "" }, /* Galactic longitude */ { "GLAT" , "DEGREE" , "" }, /* Galactic latitude */ { "ELON" , "DEGREE" , "" }, /* Ecliptic longitude */ { "ELAT" , "DEGREE" , "" }, /* Ecliptic latitude */ { "SLON" , "DEGREE" , "" }, /* Supergalactic longitude */ { "SLAT" , "DEGREE" , "" }, /* Supergalactic latitude */ { "FREQ" , "HZ" , "M/S" }, /* Frequency */ { "VELO" , "M/S" , "" }, /* Velocity axis */ { "LAMBDA", "METER" , "" }, /* Wavelength */ { "INVLAM", "1/METER", "" }, /* Inverse Wavelength */ { "LOGLAM", "LOG(M)" , "" }, /* log(wavelength) */ { "TIME" , "SECOND" , "" }, /* Time */ { "POLN" , "" , "" }, /* polarisation */ { "PARAM" , "PAR" , "" }, /* Parameter axis */ { "SAMPLE", "TICK" , "" }, /* IRDS sample axis */ { "TICK" , "TICK" , "" }, /* IRDS tick axis */ { "SDET" , "" , "" }, /* IRDS detector axis */ { "SNIP" , "" , "" } /* IRDS snip axis */ }; #define MAXNAMES (sizeof(NAMES)/sizeof(c_struct)) /* CTYPEs */ static char *PROSYS[] = { /* known projections */ "AIT", /* aitoff equal area projection */ "CYL", /* equivalent cylindrical projection */ "FLT", /* flat projection */ "TAN", /* gnomonic projection */ "SIN", /* orthographic projection */ "ARC", /* rectangular projection */ "GLS", /* transversal projection */ "NCP", /* WSRT projection */ "STG", /* stereographic projection */ "MER" /* Mercator projection */ }; #define MAXPROSYS (sizeof(PROSYS)/sizeof(char *)) /* projections */ static char *VELSYS[] = { /* known velocity systems */ "OLSR", /* optical definition, w.r.t. lsr */ "RLSR", /* radio definition, w.r.t. lsr */ "OHEL", /* optical definition, heliocentric */ "RHEL" /* radio definition, heliocentric */ }; #define MAXVELSYS (sizeof(VELSYS)/sizeof(char *)) /* vel. systems */ fint axtype_c( fchar ctype , fchar cunit , fchar dunit , fint *skysys , fint *prosys , fint *velsys ) { fint d; fint r = 0; fint k, m, n; fint lc = 0; fint lp = 0; char b[MAXBUFLEN+1]; char *a; char *c; char *p; *skysys = *prosys = *velsys = 0; /* reset */ for (k = 0; k < cunit.l; cunit.a[k++] = ' '); for (k = 0; k < dunit.l; dunit.a[k++] = ' '); m = 0; while ((m < MAXBUFLEN) && (m < ctype.l)) { b[m] = toupper( ctype.a[m] ); m++; } b[m] = 0; /* add zero byte */ a = c = b; /* start of CTYPE */ while ((*a != ' ') && (*a != '-') && (*a)) a++; /* 1st part of axis name */ lc = (fint) (a - c); /* length of CTYPE */ if (!lc) return( r ); /* empty ctype */ while (*a == '-') a++; /* skip over separators */ p = a; /* address of projection */ while ((*a != ' ') && (*a != '-') && (*a)) a++; /* 2nd part of axis name */ lp = (fint) (a - p); /* length of projection */ n = 0; /* reset */ do { /* compare CTYPE with the ones we know */ d = strncmp( c, NAMES[n++].ctype, lc ); } while (d && (n < MAXNAMES)); /*---------------------------------------*/ /* Allow unknown axis names to be of */ /* parameter type. */ /*---------------------------------------*/ if (d) n = 16; /* unknown type of axis == par */ k = strlen( NAMES[n-1].cunit ); /* copy natural units */ if (k > cunit.l ) k = cunit.l; for (m = 0; m < k; m++) cunit.a[m] = NAMES[n-1].cunit[m]; k = strlen( NAMES[n-1].dunit ); /* copy secondary units */ if (k > dunit.l ) k = dunit.l; for (m = 0; m < k; m++) dunit.a[m] = NAMES[n-1].dunit[m]; switch(n) { /* find encoded axis type */ case 1: r = 1; *skysys = 1; break; /* these are all spatial axes */ case 2: r = 2; *skysys = 1; break; case 3: r = 1; *skysys = 2; break; case 4: r = 2; *skysys = 2; break; case 5: r = 1; *skysys = 3; break; case 6: r = 2; *skysys = 3; break; case 7: r = 1; *skysys = 4; break; case 8: r = 2; *skysys = 4; break; default: r = n - 6; break; /* other axis */ } switch(r) { /* find encode projection type */ case 1: /* spatial (sky) axis */ case 2: { if (lp) { n = 0; do { /* compare projections with the ones we know */ d = strncmp( p, PROSYS[n++], lp ); } while (d && (n < MAXPROSYS)); if (d) { /* we don't know the projection */ *prosys = 4; /* assume gnomonic projection */ } else { /* we do know the projection */ *prosys = n; } } else { /* default projection is gnomonic */ *prosys = 4; } break; } case 3: { /* Frequency axis */ if (lp) { /* there is a velocity system tag */ n = 0; do { /* compare with velocity systems we know */ d = strncmp( p, VELSYS[n++], lp ); } while (d && (n < MAXVELSYS)); if (!d) switch(n) { case 1: *velsys = 1; break; case 2: *velsys = 2; break; case 3: *velsys = 1; break; case 4: *velsys = 2; break; default: break; } } break; } case 4: { /* Velocity axis */ *velsys = 2; break; } default: { break; } } return(r); } #if defined(TESTBED) void main( int argc, char *argv[] ) { fchar ctype; fchar cunit; fchar dunit; char t[MAXBUFLEN+1]; char c[MAXBUFLEN+1]; char b[MAXBUFLEN+1]; fint r; fint n; fint skysys, prosys, velsys; printf("MAXNAMES: %d\n",MAXNAMES); for (n = 1; n < argc; n++) { strncpy( t, argv[n], MAXBUFLEN ); t[MAXBUFLEN] = 0; ctype.a = t; ctype.l = strlen( t ); cunit.a = c; cunit.l = MAXBUFLEN; c[MAXBUFLEN] = 0; dunit.a = b; dunit.l = MAXBUFLEN; b[MAXBUFLEN] = 0; r = axtype_c( ctype, cunit, dunit, &skysys, &prosys, &velsys ); printf( "axtype = %ld\n", r ); printf( "cunit = %.10s\n", cunit.a ); printf( "dunit = %.10s\n", dunit.a ); printf( "skysys = %ld\n", skysys ); printf( "prosys = %ld\n", prosys ); printf( "velsys = %ld\n", velsys ); } } #endif