added warning about new temporal matcher

src/pytesmo/validation_framework/metric_calculators.py

@@ -1468,6 +1468,12 @@ class PairwiseIntercomparisonMetrics(MetadataMetrics, PairwiseMetricsMixin):
     Additionally, confidence intervals for these metrics can be calculated
     (optional).
 
+    **NOTE**: When using this within a
+      ``pytesmo.validation_framework.validation.Validation``, use
+      ``temporal_matcher=make_combined_temporal_matcher(<window>)`` as keyword
+      argument. ``make_combined_temporal_matcher`` can be imported from
+      ``pytesmo.validation_framework.temporal_matchers``.
+
     Parameters
     ----------
     min_obs : int, optional
@@ -1561,6 +1567,12 @@ class TripleCollocationMetrics(MetadataMetrics, PairwiseMetricsMixin):
     - error standard deviation
     - linear scaling/multiplicative (first-order) bias
 
+    **NOTE**: When using this within a
+      ``pytesmo.validation_framework.validation.Validation``, use
+      ``temporal_matcher=make_combined_temporal_matcher(<window>)`` as keyword
+      argument. ``make_combined_temporal_matcher`` can be imported from
+      ``pytesmo.validation_framework.temporal_matchers``.
+
     Parameters
     ----------
     refname : str

src/pytesmo/validation_framework/validation.py

@@ -7,6 +7,7 @@
 import numpy as np
 import pandas as pd
 from pygeogrids.grids import CellGrid
+import warnings
 
 from pytesmo.validation_framework.data_manager import DataManager
 from pytesmo.validation_framework.data_manager import get_result_names
@@ -121,6 +122,12 @@ def __init__(self, datasets, spatial_ref, metrics_calculators,
 
         self.temp_matching = temporal_matcher
         if self.temp_matching is None:
+            warnings.warn(
+                "You are using the default temporal matcher. If you are using one of the"
+                " newer metric calculators (PairwiseIntercomparisonMetrics,"
+                " TripleCollocationMetrics) you should probably use `make_combined_temporal_matcher`"
+                " instead. Have a look at the documentation of the metric calculators for more info."
+            )
             self.temp_matching = temporal_matchers.BasicTemporalMatching(
                 window=temporal_window).combinatory_matcher