Make data saver accept numpy type floats/ints

qcodes/dataset/measurements.py

@@ -3,7 +3,7 @@
 from time import monotonic
 from collections import OrderedDict
 from typing import (Callable, Union, Dict, Tuple, List, Sequence, cast,
-                    MutableMapping, MutableSequence, Optional)
+                    MutableMapping, MutableSequence, Optional, Any)
 from inspect import signature
 from numbers import Number
 
@@ -19,13 +19,23 @@
 log = logging.getLogger(__name__)
 
 array_like_types = (tuple, list, np.ndarray)
-non_array_like_types = (int, float, str)
 
 
 class ParameterTypeError(Exception):
     pass
 
 
+def is_number(thing: Any) -> bool:
+    """
+    Test if an object can be converted to a number
+    """
+    try:
+        float(thing)
+        return True
+    except (ValueError, TypeError):
+        return False
+
+
 class DataSaver:
     """
     The class used byt the Runner context manager to handle the
@@ -114,7 +124,7 @@ def add_result(self,
                                      f'and {array_size}')
                 else:
                     input_size = array_size
-            elif any(isinstance(value, t) for t in non_array_like_types):
+            elif is_number(value) or isinstance(value, str):
                 pass
             else:
                 raise ValueError('Wrong value type received. '