changes based on reviews

Author: charlesdong1991

pandas/plotting/_core.py

@@ -82,9 +82,9 @@ def _kind(self):
     _default_rot = 0
     orientation = None
     _pop_attributes = ['label', 'style', 'logy', 'logx', 'loglog',
-                       'mark_right', 'stacked', 'sym']
+                       'mark_right', 'stacked']
     _attr_defaults = {'logy': False, 'logx': False, 'loglog': False,
-                      'mark_right': True, 'stacked': False, 'sym': False}
+                      'mark_right': True, 'stacked': False}
 
     def __init__(self, data, kind=None, by=None, subplots=False, sharex=None,
                  sharey=False, use_index=True,
@@ -308,16 +308,20 @@ def _setup_subplots(self):
 
         axes = _flatten(axes)
 
-        if self.logx or self.loglog:
-            if self.sym:
-                [a.set_xscale('symlog') for a in axes]
-            else:
-                [a.set_xscale('log') for a in axes]
-        if self.logy or self.loglog:
-            if self.sym:
-                [a.set_yscale('symlog') for a in axes]
-            else:
-                [a.set_yscale('log') for a in axes]
+        valid_log = [False, True, 'sym']
+        for i in [self.logx, self.logy, self.loglog]:
+            if i not in valid_log:
+                raise ValueError("Wrong input for log option.")
+
+        if self.logx is True or self.loglog is True:
+            [a.set_xscale('log') for a in axes]
+        elif self.logx == 'sym' or self.loglog == 'sym':
+            [a.set_xscale('symlog') for a in axes]
+
+        if self.logy is True or self.loglog is True:
+            [a.set_yscale('log') for a in axes]
+        elif self.logy == 'sym' or self.loglog == 'sym':
+            [a.set_yscale('symlog') for a in axes]
 
         self.fig = fig
         self.axes = axes

pandas/tests/plotting/test_frame.py

@@ -231,20 +231,40 @@ def test_plot_xy(self):
     @pytest.mark.slow
     def test_logscales(self):
         df = DataFrame({'a': np.arange(100)}, index=np.arange(100))
+
         ax = df.plot(logy=True)
         self._check_ax_scales(ax, yaxis='log')
-        ax = df.plot(logy=True, sym=True)
+        assert ax.get_yscale() == 'log'
+
+        ax = df.plot(logy='sym')
         self._check_ax_scales(ax, yaxis='symlog')
+        assert ax.get_yscale() == 'symlog'
 
         ax = df.plot(logx=True)
         self._check_ax_scales(ax, xaxis='log')
-        ax = df.plot(logx=True, sym=True)
+        assert ax.get_xscale() == 'log'
+
+        ax = df.plot(logx='sym')
         self._check_ax_scales(ax, xaxis='symlog')
+        assert ax.get_xscale() == 'symlog'
 
         ax = df.plot(loglog=True)
         self._check_ax_scales(ax, xaxis='log', yaxis='log')
-        ax = df.plot(loglog=True, sym=True)
+        assert ax.get_xscale() == 'log'
+        assert ax.get_yscale() == 'log'
+
+        ax = df.plot(loglog='sym')
         self._check_ax_scales(ax, xaxis='symlog', yaxis='symlog')
+        assert ax.get_xscale() == 'symlog'
+        assert ax.get_yscale() == 'symlog'
+
+    @pytest.mark.parametrize("wrong_input", ["sm", "symlog"])
+    def test_invalid_logscale(self, wrong_input):
+        df = DataFrame({'a': np.arange(100)}, index=np.arange(100))
+
+        msg = "Wrong input for log option."
+        with pytest.raises(ValueError, match=msg):
+            df.plot(logy=wrong_input)
 
     @pytest.mark.slow
     def test_xcompat(self):