Methods __len__ (number of lines used) and __sizeof__ (total size in

bytes) implemented for columns.

python/obitools3/obidms/_obidms.pyx

@@ -276,6 +276,14 @@ cdef class OBIDMS_column :
                 self.pointer = obi_open_column(self.dms.pointer, column_name_b, version_number)
 
 
+    def __len__(self):
+        return self.pointer.header.lines_used
+    
+    
+    def __sizeof__(self):
+        return (self.pointer.header.header_size + self.pointer.header.data_size)
+    
+    
     def __iter__(self):
     
         # Declarations

python/obitools3/obidms/capi/obidmscolumn.pxd

@@ -16,7 +16,8 @@ cdef extern from "obidmscolumn.h" nogil:
     
     struct OBIDMS_column_header_t:
         bint            little_endian
-        int             header_size
+        size_t          header_size
+        size_t          data_size
         index_t         line_count
         index_t         lines_used
         index_t         nb_elements_per_line