Adding verbose attribute to GradParent to solve issue #100 (#101)

* Adding verbose attribute to GradParent to solve issue #100

* Improved the attribute docstring

* Fixed correct order of the attributes of GradParent.

modopt/opt/gradient.py

@@ -33,6 +33,8 @@ class GradParent(object):
         Method for calculating the cost (default is ``None``)
     data_type : type, optional
         Expected data type of the input data (default is ``None``)
+    verbose : bool, optional
+        Option for verbose output (default is ``True``)
 
     Examples
     --------
@@ -55,8 +57,9 @@ class GradParent(object):
     """
 
     def __init__(self, data, op, trans_op, get_grad=None, cost=None,
-                 data_type=None):
+                 data_type=None, verbose=True):
 
+        self.verbose = verbose
         self._grad_data_type = data_type
         self.obs_data = data
         self.op = op
@@ -85,7 +88,8 @@ def obs_data(self, data):
 
         if self._grad_data_type in (float, np.floating):
             data = check_float(data)
-        check_npndarray(data, dtype=self._grad_data_type, writeable=False)
+        check_npndarray(data, dtype=self._grad_data_type, writeable=False,
+                        verbose=self.verbose)
 
         self._obs_data = data