Check numpy array type

1 files changed, 15 insertions, 0 deletions

diff --git a/python/astra/pythonutils.py b/python/astra/pythonutils.py
index 715df30..ef49f97 100644
--- a/python/astra/pythonutils.py
+++ b/python/astra/pythonutils.py
@@ -29,6 +29,8 @@
 
 
 """
+import numpy as np
+
 
 def geom_size(geom, dim=None):
     """Returns the size of a volume or sinogram, based on the projection or volume geometry.
@@ -62,6 +64,19 @@ def geom_size(geom, dim=None):
 
     return s
 
+def checkArrayForLink(data):
+    """Check if a numpy array is suitable for direct usage (contiguous, etc.)
+
+    This function raises an exception if not.
+    """
+
+    if not isinstance(data, np.ndarray):
+        raise ValueError("Numpy array should be numpy.ndarray")
+    if data.dtype != np.float32:
+        raise ValueError("Numpy array should be float32")
+    if not (data.flags['C_CONTIGUOUS'] and data.flags['ALIGNED']):
+        raise ValueError("Numpy array should be C_CONTIGUOUS and ALIGNED")
+
 class GPULink(object):
     """Utility class for astra.data3d.link with a CUDA pointer