From fa080de7afc95aa1c19a6e6fc0e0708ced2eadc4 Mon Sep 17 00:00:00 2001
From: Joseph Hunkeler <jhunkeler@gmail.com>
Date: Wed, 8 Jul 2015 20:46:52 -0400
Subject: Initial commit

---
 noao/astutil/pdm/pdmfindmin.x | 57 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 57 insertions(+)
 create mode 100644 noao/astutil/pdm/pdmfindmin.x

(limited to 'noao/astutil/pdm/pdmfindmin.x')

diff --git a/noao/astutil/pdm/pdmfindmin.x b/noao/astutil/pdm/pdmfindmin.x
new file mode 100644
index 00000000..4053bf43
--- /dev/null
+++ b/noao/astutil/pdm/pdmfindmin.x
@@ -0,0 +1,57 @@
+include <mach.h>
+include <ctype.h>
+include <error.h>
+include "pdm.h"
+
+# PDM_FINDMIN -- Find the minimum value of the abscissa.
+
+int procedure pdm_findmin (pdmp, ptype, startint, endint, is, ie)
+
+pointer	pdmp			# pointer to PDM data structure
+int	ptype			# plot type
+double	startint, endint	# start and end ordinates
+int	is, ie			# start and end indexs
+
+double	miny, dy, dx
+int	i, isave, npt
+pointer	xpt, ypt
+
+begin
+	# Dereference npt.
+	npt = PDM_NPT(pdmp)
+
+	# Dereference the appropriate abcissa and ordinate.
+	switch (ptype) {
+	case DATAPLOT:
+	    xpt = PDM_XP(pdmp)
+	    ypt = PDM_DYP(pdmp)
+	case THETAPPLOT:
+	    xpt = PDM_XTHP(pdmp)
+	    ypt = PDM_YTHP(pdmp)
+	case THETAFPLOT:
+	    ypt = PDM_YTHP(pdmp)
+	    xpt = PDM_XTHP(pdmp)
+	case PHASEPLOT:
+	    ypt = PDM_YPHP(pdmp)
+	    xpt = PDM_XPHP(pdmp)
+	}
+
+	# Search the abscissas between startint and endint
+	# for the minimum value.
+
+	isave = 1
+	miny = MAX_DOUBLE
+	do i = is, ie {
+	    dx = Memd[xpt+i-1]
+	    dy = Memd[ypt+i-1]
+	    if (dx > startint && dx < endint) {
+		if (dy < miny) {
+	    	    miny = dy
+	    	    isave = i
+		}
+	    }
+	}
+
+	# Return the corresponding index value.
+	return (isave)
+end
-- 
cgit