Split 'get_xygrid()' from 'make_expmap.py' to 'acispy/image.py'

1 files changed, 22 insertions, 0 deletions

diff --git a/acispy/image.py b/acispy/image.py
new file mode 100644
index 0000000..0bcaf67
--- /dev/null
+++ b/acispy/image.py
@@ -0,0 +1,22 @@
+# Copyright (c) 2017 Weitian LI <liweitianux@live.com>
+# MIT license
+
+"""
+FITS image utilities
+"""
+
+import subprocess
+
+
+def get_xygrid(image):
+    """
+    Get the ``xygrid`` of the input image.
+    """
+    subprocess.check_call(["punlearn", "get_sky_limits"])
+    subprocess.check_call([
+        "get_sky_limits", "image=%s" % image, "verbose=0"
+    ])
+    xygrid = subprocess.check_output([
+        "pget", "get_sky_limits", "xygrid"
+    ]).decode("utf-8").strip()
+    return xygrid