REF: use named funcs instead of lambdas (pandas-dev#29841)

Author: jbrockmendel

pandas/core/generic.py

@@ -10226,7 +10226,7 @@ def compound(self, axis=None, skipna=None, level=None):
             name2,
             axis_descr,
             "minimum",
-            lambda y, axis: np.minimum.accumulate(y, axis),
+            np.minimum.accumulate,
             "min",
             np.inf,
             np.nan,
@@ -10239,7 +10239,7 @@ def compound(self, axis=None, skipna=None, level=None):
             name2,
             axis_descr,
             "sum",
-            lambda y, axis: y.cumsum(axis),
+            np.cumsum,
             "sum",
             0.0,
             np.nan,
@@ -10252,7 +10252,7 @@ def compound(self, axis=None, skipna=None, level=None):
             name2,
             axis_descr,
             "product",
-            lambda y, axis: y.cumprod(axis),
+            np.cumprod,
             "prod",
             1.0,
             np.nan,
@@ -10265,7 +10265,7 @@ def compound(self, axis=None, skipna=None, level=None):
             name2,
             axis_descr,
             "maximum",
-            lambda y, axis: np.maximum.accumulate(y, axis),
+            np.maximum.accumulate,
             "max",
             -np.inf,
             np.nan,