From 57e00fc8ac9b9143dd47acf97346db16ae53c26f Mon Sep 17 00:00:00 2001
From: dencheva <dencheva@stsci.edu>
Date: Wed, 22 Sep 2010 19:30:12 +0000
Subject: Moved utils from stwcs to updatewcs

git-svn-id: http://svn.stsci.edu/svn/ssb/stsci_python/stsci_python/trunk/stwcs@10375 fe389314-cf27-0410-b35b-8c050e845b92
---
 updatewcs/utils.py | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)
 create mode 100644 updatewcs/utils.py

(limited to 'updatewcs/utils.py')

diff --git a/updatewcs/utils.py b/updatewcs/utils.py
new file mode 100644
index 0000000..29ba5f3
--- /dev/null
+++ b/updatewcs/utils.py
@@ -0,0 +1,28 @@
+from __future__ import division # confidence high
+
+def diff_angles(a,b):
+    """ 
+    Perform angle subtraction a-b taking into account
+    small-angle differences across 360degree line. 
+    """
+    
+    diff = a - b
+    
+    if diff > 180.0:
+        diff -= 360.0
+
+    if diff < -180.0:
+        diff += 360.0
+    
+    return diff
+
+def getBinning(fobj, extver=1):
+    # Return the binning factor
+    binned = 1
+    if fobj[0].header['INSTRUME'] == 'WFPC2':
+        mode = fobj[0].header.get('MODE', "")
+        if mode == 'AREA': binned = 2
+    else:
+        binned = fobj['SCI', extver].header.get('BINAXIS',1)
+    return binned
+
-- 
cgit