Plotter cleanup

ansys/dpf/core/errors.py

@@ -1,5 +1,31 @@
 from grpc._channel import _InactiveRpcError, _MultiThreadedRendezvous
 
+_COMPLEX_PLOTTING_ERROR_MSG = """
+Complex fields can not be plotted. Use operators to get the amplitude
+or the result at a defined sweeping phase before plotting.
+"""
+
+_FIELD_CONTAINER_PLOTTING_MSG = """"
+This fields_container contains multiple fields.  Only one time-step
+result can be plotted at a time.  Extract a field with
+``fields_container[index]``.
+"""
+
+
+class ComplexPlottingError(ValueError):
+    """Raised when attempting to plot a field with complex data"""
+
+    def __init__(self, msg=_COMPLEX_PLOTTING_ERROR_MSG):
+        ValueError.__init__(self, msg)
+
+
+class FieldContainerPlottingError(ValueError):
+    """Raised when attempting to plot a fields_container containing
+    multiple fields."""
+
+    def __init__(self, msg=_FIELD_CONTAINER_PLOTTING_MSG):
+        ValueError.__init__(self, msg)
+
 
 class InvalidANSYSVersionError(RuntimeError):
     """Raised when ANSYS is an invalid version"""