Rename map

packages/vaex-core/vaex/dataframe.py

@@ -3664,8 +3664,24 @@ def add_virtual_column(self, name, expression, unique=False):
         self._save_assign_expression(valid_name)
         self.signal_column_changed.emit(self, valid_name, "add")
 
-    def rename(self, name, new_name, unique=False):
+    def _renames(self, names, unique=False):
         """Renames a column or variable, and rewrite expressions such that they refer to the new name"""
+        columns = self.get_column_names()
+        ret = []
+        for name, new_name in names.items():
+            if name == new_name:
+                continue
+            if name not in columns:
+                continue
+            new_name = vaex.utils.find_valid_name(new_name, used=None if not unique else self.get_column_names(hidden=True))
+            self._rename(name, new_name, rename_meta_data=True)
+            ret.append(new_name)
+        return ret
+
+    def rename(self, name, new_name=None, unique=False):
+        """Renames a column or variable, and rewrite expressions such that they refer to the new name"""
+        if isinstance(name, dict):
+            return self._renames(name, unique=unique)
         if name == new_name:
             return
         new_name = vaex.utils.find_valid_name(new_name, used=None if not unique else self.get_column_names(hidden=True))

tests/rename_test.py

@@ -1,5 +1,17 @@
 from common import *
 
+
+def test_renames(df_local):
+    ds = df_local
+    new_columns = ds.rename({'x': 'x1', 'y': 'y1'})
+    assert new_columns == ['x1', 'y1']
+    current_columns = ds.get_column_names()
+    for column in new_columns:
+        assert column in current_columns
+    for column in ['x', 'y']:
+        assert column not in current_columns
+
+
 def test_rename(ds_filtered):
     ds = ds_filtered
     ds['r'] = ds.x