1 files changed, 29 insertions, 0 deletions
diff --git a/noao/onedspec/identify/idnearest.x b/noao/onedspec/identify/idnearest.x
new file mode 100644
index 00000000..41aa4c61
--- /dev/null
+++ b/noao/onedspec/identify/idnearest.x
@@ -0,0 +1,29 @@
+include	"identify.h"
+
+# ID_NEAREST -- Find the nearest feature to a given coordinate.
+
+procedure id_nearest (id, fitnear)
+
+pointer	id			# ID pointer
+double	fitnear			# Coordinate to find nearest feature
+
+int	i
+double	delta, delta1
+
+begin
+	if (ID_NFEATURES(id) < 1) {
+	    ID_CURRENT(id) = 0
+	    return
+	}
+
+	ID_CURRENT(id) = 1
+	delta = abs (FIT(id,1) - fitnear)
+
+	do i = 2, ID_NFEATURES(id) {
+	    delta1 = abs (FIT(id,i) - fitnear)
+	    if (delta1 < delta) {
+		ID_CURRENT(id) = i
+		delta = delta1
+	    }
+	}
+end