Changeset 1172

Timestamp:

17/01/09 00:55:20 (3 years ago)

Author:

Paul Kienzle

Message:

Improve handling of CDF0.0 and other HDF4 problems. Refs #149.

Location:

trunk/bindings/python

Files:

• nxs/napi.py (modified) (7 diffs)
• nxstest.py (modified) (1 diff)

trunk/bindings/python/nxs/napi.py

@@ -1 @@
-# This program is public domain
-
+# This program is public domain 
 # Author: Paul Kienzle
 
@@ -107 +106 @@
   nxs.MAXNAMELEN  - names must be shorter than this
   nxs.MAXPATHLEN  - total path length must be shorter than this
-
+  nxs.H4SKIP - class names that may appear in HDF4 files but can be ignored
 
 Caveats
@@ -123 +122 @@
 .. _NAPI:  http://www.nexusformat.org/Application_Program_Interface
 """
-__all__ = ['UNLIMITED', 'MAXRANK', 'MAXNAMELEN','MAXPATHLEN',
+__all__ = ['UNLIMITED', 'MAXRANK', 'MAXNAMELEN','MAXPATHLEN','H4SKIP',
            'NeXus','NeXusError','open']
 
@@ -156 +155 @@
 MAXNAMELEN=64
 MAXPATHLEN=1024 # inferred from code
+
+# bogus groups; these groups are ignored in HDFView from NCSA.
+H4SKIP = ['CDF0.0','_HDF_CHK_TBL_','Attr0.0',
+          'RIG0.0','RI0.0', 'RIATTR0.0N','RIATTR0.0C']
 
 # HDF data types from numpy types
@@ -602 +605 @@
         since getinfo returns shape and storage, both of which are required
         to read the data.
+
+        Note that HDF4 files can have entries in the file with classes
+        that don't need to be processed.  If the file follows the standard
+        NeXus DTDs then skip any entry for which nxclass.startswith('NX') 
+        is False.  For non-conforming files, skip those entries with 
+        nxclass in nxs.H4SKIP.
         """
         name = ctypes.create_string_buffer(MAXNAMELEN)
@@ -630 +639 @@
         This does not correspond to an existing NeXus API function,
         but instead combines the work of initgroupdir/getnextentry
-        and open/close on data and group.
+        and open/close on data and group.  Entries in nxs.H4SKIP are
+        ignored.
         """
         # To preserve the semantics we must read in the whole list
@@ -642 +652 @@
         L = []
         for i in range(n):
-            L.append(self.getnextentry())
+            name,nxclass = self.getnextentry()
+            if nxclass not in H4SKIP:
+                L.append((name,nxclass))
         for name,nxclass in L:
             self.openpath(path)  # Reset the file cursor

trunk/bindings/python/nxstest.py

@@ -45 +45 @@
         print "%(prefix)s@%(attr)s: %(value)s" % locals()
     for name,nxclass in file.entries():
-        if nxclass.startswith("CDF"): continue # Root has an extra CDF class
         if nxclass == "SDS":
             shape,dtype = file.getinfo()