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authorJoe Hunkeler <jhunkeler@gmail.com>2015-08-11 16:51:37 -0400
committerJoe Hunkeler <jhunkeler@gmail.com>2015-08-11 16:51:37 -0400
commit40e5a5811c6ffce9b0974e93cdd927cbcf60c157 (patch)
tree4464880c571602d54f6ae114729bf62a89518057 /noao/astutil/pdm/pdmminmaxp.x
downloadiraf-osx-40e5a5811c6ffce9b0974e93cdd927cbcf60c157.tar.gz
Repatch (from linux) of OSX IRAF
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+include <mach.h>
+include <ctype.h>
+include <error.h>
+include "pdm.h"
+
+# PDM_MINMAXP -- Calculate the minimum and maximum periods automatically.
+
+procedure pdm_minmaxp (pdmp)
+
+pointer pdmp # pointer to PDM data structure
+
+int npt, i
+double minp, maxp
+pointer sep, sp
+
+begin
+ call smark (sp)
+ npt = PDM_NPT(pdmp)
+
+ # Allocate an array of separations and fill it. Find the minimum
+ # separation as we go.
+
+ call salloc (sep, npt-1, TY_DOUBLE)
+ maxp = PDM_X(pdmp,npt) - PDM_X(pdmp,1)
+ minp = maxp
+ do i = 1, npt-1 {
+ Memd[sep+i-1] = PDM_X(pdmp,i+1) - PDM_X(pdmp,i)
+ if (Memd[sep+i-1] < minp)
+ minp = Memd[sep+i-1]
+ }
+
+ # Set minp equal to twice this minimum (Nyquist criterion). Set fmax.
+ PDM_PMIN(pdmp) = 2.0d+0 * minp
+ if (PDM_PMIN(pdmp) != 0.0d+0)
+ PDM_FMAX(pdmp) = 1.0d+0/PDM_PMIN(pdmp)
+
+ # Set maxp equal to 4 times maxp. Set fmin.
+ PDM_PMAX(pdmp) = 4.0d+0 * maxp
+ if (PDM_PMAX(pdmp) != 0.0d+0)
+ PDM_FMIN(pdmp) = 1.0d+0/PDM_PMAX(pdmp)
+
+ call sfree (sp)
+end