1 files changed, 78 insertions, 0 deletions
diff --git a/src/gen_cheb.cpp b/src/gen_cheb.cpp
new file mode 100644
index 00000000..ab16b409
--- /dev/null
+++ b/src/gen_cheb.cpp
@@ -0,0 +1,78 @@
+/* generates 'T' option output */
+#define PJ_LIB__
+#include "projects.h"
+#include <stdio.h>
+#include <string.h>
+#include <errno.h>
+#include "emess.h"
+#ifndef COEF_LINE_MAX
+#define COEF_LINE_MAX 50
+#endif
+
+/* FIXME: put the declaration in a header. Also used in proj.c */
+void gen_cheb(int inverse, projUV (*proj)(projUV), char *s, PJ *P,
+              int iargc, char **iargv);
+extern void p_series(Tseries *, FILE *, char *);
+
+void gen_cheb(int inverse, projUV (*proj)(projUV), char *s, PJ *P,
+              int iargc, char **iargv) {
+	long NU = 15, NV = 15;
+	int errin = 0, pwr;
+	long res = -1;
+	char *arg, fmt[32];
+	projUV low, upp, resid;
+	Tseries *F;
+	double (*input)(const char *, char **);
+
+	input = inverse ? strtod : dmstor;
+	if (*s) low.u = input(s, &s); else { low.u = 0; ++errin; }
+	if (*s == ',') upp.u = input(s+1, &s); else { upp.u = 0; ++errin; }
+	if (*s == ',') low.v = input(s+1, &s); else { low.v = 0; ++errin; }
+	if (*s == ',') upp.v = input(s+1, &s); else { upp.v = 0; ++errin; }
+	if (errin)
+		emess(16,"null or absent -T parameters");
+	if (*s == ',') if (*++s != ',') res = strtol(s, &s, 10);
+	if (*s == ',') if (*++s != ',') NU = strtol(s, &s, 10);
+	if (*s == ',') if (*++s != ',') NV = strtol(s, &s, 10);
+	pwr = s && *s && !strcmp(s, ",P");
+	(void)printf("#proj_%s\n#    run-line:\n",
+		pwr ? "Power" : "Chebyshev");
+	if (iargc > 0) { /* proj execution audit trail */
+		int n = 0, L;
+
+		for ( ; iargc ; --iargc) {
+			arg = *iargv++;
+			if (*arg != '+') {
+				if (!n) { putchar('#'); ++n; }
+				(void)printf(" %s%n",arg, &L);
+				if ((n += L) > COEF_LINE_MAX) { putchar('\n'); n = 0; }
+			}
+		}
+		if (n) putchar('\n');
+	}
+	(void)printf("# projection parameters\n");
+	pj_pr_list(P);
+	if (low.u == upp.u || low.v >= upp.v)
+		emess(16,"approx. argument range error");
+	if (low.u > upp.u)
+		low.u -= M_TWOPI;
+	if (NU < 2 || NV < 2 || NU > INT_MAX || NV > INT_MAX)
+		emess(16,"approx. work dimensions (%ld %ld) too small or large",NU,NV);
+	if (!(F = mk_cheby(low, upp, pow(10., (double)res)*.5, &resid, proj,
+		(int)NU, (int)NV, pwr)))
+		emess(16,"generation of approx failed\nreason: %s\n",
+			pj_strerrno(errno));
+	(void)printf("%c,%.12g,%.12g,%.12g,%.12g,%.12g\n",inverse?'I':'F',
+		P->lam0*RAD_TO_DEG,
+		low.u*(inverse?1.:RAD_TO_DEG),upp.u*(inverse?1.:RAD_TO_DEG),
+		low.v*(inverse?1.:RAD_TO_DEG),upp.v*(inverse?1.:RAD_TO_DEG));
+	if (pwr)
+		strcpy(fmt, "%.15g");
+	else if (res <= 0)
+		(void)sprintf(fmt,"%%.%ldf",-res+1);
+	else
+		(void)strcpy(fmt,"%.0f");
+	p_series(F, stdout, fmt);
+	(void)printf("# |u,v| sums %g %g\n#end_proj_%s\n",
+		resid.u, resid.v, pwr ? "Power" : "Chebyshev");
+}