diff --git a/pynemo/reader/ncml.py b/pynemo/reader/ncml.py
index 804f1f65f8a585428d8b758340dc4a5f705d9a3a..5d1e4504f79954c920a5c57b174a9d98e3a8d86e 100644
--- a/pynemo/reader/ncml.py
+++ b/pynemo/reader/ncml.py
@@ -225,7 +225,7 @@ class Variable(object):
             retval = data_array.copyToNDJavaArray() 
             #TODO: copy it into numpy instead of Java array and then convert to numpy
             # convert to numpy array
-            retval = np.asarray(retval)
+            retval = np.asarray(retval, dtype='float')
             self.logger.info(retval.shape)
             if np_input: #if an array is passed as selection
                 ret_dim_list = ()