Added docstring. Changes made in tests and image.py.

refs planetarypy#60

planetaryimage/image.py

@@ -20,28 +20,21 @@ def open(cls, filename):
             Name of file to read as an image file.  This file may be gzip
             (``.gz``) or bzip2 (``.bz2``) compressed.
         """
-        if isinstance(filename, numpy.ndarray):
-            error_msg = (
-                'A file like object is expected for stream. '
-                'Use PDS3Image(numpy_array) to create a PDS3Image object.'
-            )
-            raise TypeError(error_msg)
+        if filename.endswith('.gz'):
+            fp = gzip.open(filename, 'rb')
+            try:
+                return cls(fp, filename, compression='gz')
+            finally:
+                fp.close()
+        elif filename.endswith('.bz2'):
+            fp = bz2.BZ2File(filename, 'rb')
+            try:
+                return cls(fp, filename, compression='bz2')
+            finally:
+                fp.close()
         else:
-            if filename.endswith('.gz'):
-                fp = gzip.open(filename, 'rb')
-                try:
-                    return cls(fp, filename, compression='gz')
-                finally:
-                    fp.close()
-            elif filename.endswith('.bz2'):
-                fp = bz2.BZ2File(filename, 'rb')
-                try:
-                    return cls(fp, filename, compression='bz2')
-                finally:
-                    fp.close()
-            else:
-                with open(filename, 'rb') as fp:
-                    return cls(fp, filename)
+            with open(filename, 'rb') as fp:
+                return cls(fp, filename)
 
     def __init__(self, stream_string_or_array, filename=None, compression=None):
         """Create an Image object.
@@ -66,7 +59,7 @@ def __init__(self, stream_string_or_array, filename=None, compression=None):
             raise TypeError(error_msg % type(self).__name__)
 
         if isinstance(stream_string_or_array, numpy.ndarray):
-            self.filename = 'numpy_array'
+            self.filename = None
             self.compression = None
             self.data = stream_string_or_array
             self.label = self._create_label(stream_string_or_array)

planetaryimage/pds3image.py

@@ -123,6 +123,21 @@ class PDS3Image(PlanetaryImage):
     }
 
     def _save(self, file_to_write, overwrite):
+        """Save PDS3Image object as PDS3 file.
+
+        Parameters
+        ----------
+        Overwrite: Use this keyword to save image with same filename.
+
+        Examples
+        --------
+
+        >>> from planetaryimage import PDS3Image
+        >>> image = PDS3Image.open('tests/mission_data/2p129641989eth0361p2600r8m1.img')
+        >>> image.save('temp.IMG')
+        >>> image.save('temp.IMG', overwrite=True)
+
+        """
         if overwrite:
             file_to_write = self.filename
         elif os.path.isfile(file_to_write):
@@ -167,6 +182,15 @@ def _save(self, file_to_write, overwrite):
         stream.close()
 
     def _create_label(self, array):
+        """Create sample PDS3 label for NumPy Array.
+        It is called by 'image.py' to create PDS3Image object
+        from Numpy Array.
+
+        Examples
+        --------
+        >>> self.label = _create_label(array)
+
+        """
         if len(array.shape) == 3:
             bands = array.shape[0]
             lines = array.shape[1]
@@ -197,6 +221,19 @@ def _create_label(self, array):
         return self._update_label(label_module, array)
 
     def _update_label(self, label, array):
+        """Update PDS3 label for NumPy Array.
+        It is called by '_create_label' to update label values.
+        e.g.
+        - ^IMAGE, RECORD_BYTES
+        - STANDARD_DEVIATION
+        - MAXIMUM, MINIMUM
+        - MEDIAN, MEAN
+
+        Examples
+        --------
+        >>> self.label = self._update_label(label, array)
+
+        """
         maximum = float(numpy.max(array))
         mean = float(numpy.mean(array))
         median = float(numpy.median(array))

tests/test_pds3file.py

@@ -183,9 +183,8 @@ def test_image_save_float_to_int():
 
 
 def test_numpy_array_save_i2():
-    image = PDS3Image.open(filename)
     array = numpy.arange(100, dtype='>i2')
-    array = array.reshape(10, 10)
+    array = array.reshape(1, 10, 10)
     temp = PDS3Image(array)
     temp.save('Temp_Image.IMG')
     image_temp = PDS3Image.open('Temp_Image.IMG')
@@ -196,14 +195,13 @@ def test_numpy_array_save_i2():
     assert image_temp.dtype == '>i2'
     assert image_temp.shape == (1, 10, 10)
     assert image_temp.size == 100
-    assert_almost_equal(image_temp.data, image.data)
+    assert_almost_equal(image_temp.data, array)
     os.remove('Temp_Image.IMG')
 
 
 def test_numpy_array_save_f4():
-    image = PDS3Image.open(filename_float)
     array = numpy.arange(100)
-    array = array.reshape(10, 10)
+    array = array.reshape(1, 10, 10)
     array = array * 1.5
     array = array.astype('>f4')
     temp = PDS3Image(array)
@@ -216,7 +214,7 @@ def test_numpy_array_save_f4():
     assert image_temp.dtype == '>f4'
     assert image_temp.shape == (1, 10, 10)
     assert image_temp.size == 100
-    assert_almost_equal(image_temp.data, image.data)
+    assert_almost_equal(image_temp.data, array)
     os.remove('Temp_Image.IMG')