when converting from wavelength to filter and using lookup table to d…

…o so, round the value in the lookup table in the same fashion as the rounding of the given wavelength to avoid rounding issues when trying to compare floating-point numbers

svn path=/trunk/perlmods/; revision=9403

WaveBand.pm

@@ -102,14 +102,14 @@ my %FILTERS = (
 			   Q =>20.0,
 			  },
 	       WFCAM => {
-			 "Z"     => "0.83",
-			 "Y"     => "0.97",
-			 "J"     => "1.17",
-			 "H"     => "1.49",
-			 "K"     => "2.03",
-			 "1-0S1" => "2.111",
-			 "BGamma"=> "2.155",
-			 "Blank" => "0",
+			 "Z"     => 0.83,
+			 "Y"     => 0.97,
+			 "J"     => 1.17,
+			 "H"     => 1.49,
+			 "K"     => 2.03,
+			 "1-0S1" => 2.111,
+			 "BGamma"=> 2.155,
+			 "Blank" => 0,
 			 },
 	       IRCAM => {
 			 "J98" =>     "1.250" ,
@@ -866,6 +866,7 @@ sub _convert_to {
     # Inverse cm
     $output = 1.0 / ( $lambda / 10_000);
   } elsif ($category eq 'filter') {
+
     # This is slightly harder since we know the value but
     # not the key. Go through each hash looking for a matching
     # key. If we know the instrument we start looking there
@@ -880,16 +881,20 @@ sub _convert_to {
     # the base wavelegnth to use 8 significant figures
     $lambda = sprintf("%8e", $lambda);
 
-    OUTER: foreach my $inst (@search) {
-	next unless exists $FILTERS{$inst};
-	my $hash = $FILTERS{$inst};
-	for my $key (keys %{ $hash }) {
-	  if ($hash->{$key} == $lambda) {
-	    $output = $key;
-	    last OUTER;
-	  }
-	}
+  OUTER: foreach my $inst (@search) {
+      next unless exists $FILTERS{$inst};
+      my $hash = $FILTERS{$inst};
+      for my $key (keys %{ $hash }) {
+        # Make sure we use the same rounding scheme on the values
+        # returned from the hash, so we don't have to worry about
+        # rounding issues fouling things up (like saying 8.3e-1 !=
+        # 0.83).
+        if (sprintf("%8e", $hash->{$key} ) eq $lambda) {
+          $output = $key;
+          last OUTER;
+        }
       }
+    }
   }
 
   return $output;