diff --git a/pandas/core/common.py b/pandas/core/common.py
index a3fba762509f1..92e4e23ce958e 100644
--- a/pandas/core/common.py
+++ b/pandas/core/common.py
@@ -122,6 +122,24 @@ def is_bool_indexer(key):
     return False
 
 
+def cast_scalar_indexer(val):
+    """
+    To avoid numpy DeprecationWarnings, cast float to integer where valid.
+
+    Parameters
+    ----------
+    val : scalar
+
+    Returns
+    -------
+    outval : scalar
+    """
+    # assumes lib.is_scalar(val)
+    if lib.is_float(val) and val == int(val):
+        return int(val)
+    return val
+
+
 def _not_none(*args):
     """Returns a generator consisting of the arguments that are not None"""
     return (arg for arg in args if arg is not None)
diff --git a/pandas/core/indexes/base.py b/pandas/core/indexes/base.py
index 710c9d0e296c9..b2b6e02e908c5 100644
--- a/pandas/core/indexes/base.py
+++ b/pandas/core/indexes/base.py
@@ -2047,6 +2047,7 @@ def __getitem__(self, key):
         promote = self._shallow_copy
 
         if is_scalar(key):
+            key = com.cast_scalar_indexer(key)
             return getitem(key)
 
         if isinstance(key, slice):
diff --git a/pandas/core/indexes/multi.py b/pandas/core/indexes/multi.py
index 955f1461075f9..90743033e492c 100644
--- a/pandas/core/indexes/multi.py
+++ b/pandas/core/indexes/multi.py
@@ -1551,6 +1551,8 @@ def __setstate__(self, state):
 
     def __getitem__(self, key):
         if is_scalar(key):
+            key = com.cast_scalar_indexer(key)
+
             retval = []
             for lev, lab in zip(self.levels, self.labels):
                 if lab[key] == -1:
diff --git a/pandas/io/formats/style.py b/pandas/io/formats/style.py
index 6501717f715cb..b175dd540a518 100644
--- a/pandas/io/formats/style.py
+++ b/pandas/io/formats/style.py
@@ -1033,10 +1033,14 @@ def css_bar(start, end, color):
         def css(x):
             if pd.isna(x):
                 return ''
+
+            # avoid deprecated indexing `colors[x > zero]`
+            color = colors[1] if x > zero else colors[0]
+
             if align == 'left':
-                return css_bar(0, x, colors[x > zero])
+                return css_bar(0, x, color)
             else:
-                return css_bar(min(x, zero), max(x, zero), colors[x > zero])
+                return css_bar(min(x, zero), max(x, zero), color)
 
         if s.ndim == 1:
             return [css(x) for x in normed]
diff --git a/pandas/util/testing.py b/pandas/util/testing.py
index 01fafd7219382..f785ec35f52db 100644
--- a/pandas/util/testing.py
+++ b/pandas/util/testing.py
@@ -2431,7 +2431,7 @@ def assert_raises_regex(_exception, _regexp, _callable=None,
 
     You can also use this in a with statement.
 
-    >>> with assert_raises_regex(TypeError, 'unsupported operand type\(s\)'):
+    >>> with assert_raises_regex(TypeError, r'unsupported operand type\(s\)'):
     ...     1 + {}
     >>> with assert_raises_regex(TypeError, 'banana'):
     ...     'apple'[0] = 'b'