Merge pull request #1756 from larrymanley/aiaprep_fix

Fix for aiaprep - issue #1691

.gitignore

@@ -1,4 +1,5 @@
 .DS_Store
+.idea
 .pydevproject
 .settings
 .project

CHANGELOG.md

@@ -1,5 +1,6 @@
 Latest
 ------
+* Fixed `aiaprep` to return properly sized map.
 
 * Deprecation warnings fixed when using image coalignment.
 * Sunpy is now Python 3.x compatible (3.4 and 3.5).

sunpy/instr/aia.py

@@ -2,6 +2,7 @@
 """
 Provides processing routines for data captured with the AIA instrument on SDO.
 """
+import numpy as np
 import astropy.units as u
 
 from sunpy.map.sources.sdo import AIAMap
@@ -49,7 +50,15 @@ def aiaprep(aiamap):
         scale = 0.6*u.arcsec # pragma: no cover # can't test this because it needs a full res image
     scale_factor = aiamap.scale.x / scale
 
-    newmap = aiamap.rotate(recenter=True, scale=scale_factor.value, missing=aiamap.min())
+    tempmap = aiamap.rotate(recenter=True, scale=scale_factor.value, missing=aiamap.min())
+
+    # extract center from padded aiamap.rotate output
+    # crpix1 and crpix2 will be equal (recenter=True), as aiaprep does not work with submaps
+    center = np.floor(tempmap.meta['crpix1'])
+    range_side = (center + np.array([-1, 1]) * aiamap.data.shape[0] / 2) * u.pix
+    newmap = tempmap.submap(range_side, range_side)
+
+    newmap.meta['r_sun'] = newmap.meta['rsun_obs'] / newmap.meta['cdelt1']
     newmap.meta['lvl_num'] = 1.5
 
     return newmap

sunpy/instr/tests/test_aia.py

@@ -16,6 +16,8 @@
 def test_aiaprep():
     # Test that header info for the map has been correctly updated
     # Check all of these for Map attributes and .meta values?
+    # Check array shape
+    assert prep_map.data.shape == original.data.shape
     # Check crpix values
     assert prep_map.meta['crpix1'] == prep_map.data.shape[1]/2.0 + 0.5
     assert prep_map.meta['crpix2'] == prep_map.data.shape[0]/2.0 + 0.5