use input 'label' if specified #7

src/openeo_processes/arrays.py

@@ -9,6 +9,7 @@
 from openeo_processes.errors import ArrayElementNotAvailable
 from openeo_processes.errors import ArrayElementParameterMissing
 from openeo_processes.errors import ArrayElementParameterConflict
+from openeo_processes.errors import GenericError
 
 ########################################################################################################################
 # Array Contains Process
@@ -109,7 +110,7 @@ def exec_num():
         pass
 
     @staticmethod
-    def exec_np(data, index=None, label=None, dimension=0, return_nodata=False):
+    def exec_np(data, index=None, label=None, dimension=0, return_nodata=False, labels=None):
         """
         Returns the element with the specified index or label from the array. Either the parameter `index` or `label`
         must be specified, otherwise the `ArrayElementParameterMissing` exception is thrown. If both parameters are set
@@ -128,6 +129,8 @@ def exec_np(data, index=None, label=None, dimension=0, return_nodata=False):
         return_nodata : bool, optional
             By default this process throws an `ArrayElementNotAvailable` exception if the index or label is invalid.
             If you want to return np.nan instead, set this flag to `True`.
+        labels : np.array, optional
+            The available labels.
 
         Returns
         -------
@@ -144,8 +147,10 @@ def exec_np(data, index=None, label=None, dimension=0, return_nodata=False):
             Only `index` or `labels` allowed to be set.
 
         """
-        ArrayElement._check_input(index, label)
-
+        ArrayElement._check_input(index, label, labels)
+        if label:
+            # Convert label to index, using labels
+            index = labels.tolist().index(label)
         if index >= data.shape[dimension]:
             if not return_nodata:
                 raise ArrayElementNotAvailable()
@@ -166,7 +171,7 @@ def exec_da():
         pass
 
     @staticmethod
-    def _check_input(index, label):
+    def _check_input(index, label, labels):
         """
         Checks if `index` and `label` are given correctly.
 
@@ -179,6 +184,8 @@ def _check_input(index, label):
             The zero-based index of the element to retrieve (default is 0).
         label : int or str, optional
             The label of the element to retrieve.
+        labels : np.array, optional
+            The available labels.
 
         Raises
         ------
@@ -193,6 +200,10 @@ def _check_input(index, label):
 
         if index is None and label is None:
             raise ArrayElementParameterMissing()
+
+        if label and labels is None:
+            msg = "Parameter 'labels' is needed when specifying input parameter 'label'."
+            raise GenericError(msg)
 
 
 ########################################################################################################################

src/openeo_processes/errors.py

@@ -39,3 +39,9 @@ def __str__(self):
         return self.message
 
 
+class GenericError(Exception):
+    def __init__(self, msg):
+        self.message = msg
+
+    def __str__(self):
+        return self.message

tests/test_arrays.py

@@ -24,6 +24,7 @@ def test_array_contains(self):
 
     def test_array_element(self):
         """ Tests `array_element` function. """
+        assert oeop.array_element([9, 8], label="B", labels=np.array(["A", "B"])) == 8
         assert oeop.array_element([9, 8, 7, 6, 5], index=2) == 7
         assert oeop.array_element(["A", "B", "C"], index=0) == "A"
         assert np.isnan(oeop.array_element([], index=0, return_nodata=True))