FIX: make matplotlib actually optional

Author: gdementen

larray/util/plot.py

@@ -1,37 +1,40 @@
 import numpy as np
-from matplotlib.ticker import MaxNLocator
 
+try:
+    from matplotlib.ticker import MaxNLocator
 
-class MaxNMultipleWithOffsetLocator(MaxNLocator):
-    def __init__(self, nbins=None, offset=0.5, **kwargs):
-        super().__init__(nbins, **kwargs)
-        self.offset = offset
+    class MaxNMultipleWithOffsetLocator(MaxNLocator):
+        def __init__(self, nbins=None, offset=0.5, **kwargs):
+            super().__init__(nbins, **kwargs)
+            self.offset = offset
 
-    def tick_values(self, vmin, vmax):
-        # matplotlib calls them vmin and vmax but they are actually the limits and vmin can be > vmax
-        invert = vmin > vmax
-        if invert:
-            vmin, vmax = vmax, vmin
+        def tick_values(self, vmin, vmax):
+            # matplotlib calls them vmin and vmax but they are actually the limits and vmin can be > vmax
+            invert = vmin > vmax
+            if invert:
+                vmin, vmax = vmax, vmin
 
-        max_desired_ticks = self._nbins
-        # not + 1 because we place ticks in the middle
-        num_ticks = vmax - vmin
-        desired_numticks = min(num_ticks, max_desired_ticks)
-        if desired_numticks < num_ticks:
-            step = np.ceil(num_ticks / desired_numticks)
-        else:
-            step = 1
-        vmin = int(vmin)
-        vmax = int(vmax)
-        # when we have an offset, we do not add 1 to vmax because we place ticks in the middle
-        # (by adding the offset), and would result in the last "tick" being outside the limits
-        stop = vmax + 1 if self.offset == 0 else vmax
-        new_ticks = np.arange(vmin, stop, step)
-        if invert:
-            new_ticks = new_ticks[::-1]
-        return new_ticks + self.offset
+            max_desired_ticks = self._nbins
+            # not + 1 because we place ticks in the middle
+            num_ticks = vmax - vmin
+            desired_numticks = min(num_ticks, max_desired_ticks)
+            if desired_numticks < num_ticks:
+                step = np.ceil(num_ticks / desired_numticks)
+            else:
+                step = 1
+            vmin = int(vmin)
+            vmax = int(vmax)
+            # when we have an offset, we do not add 1 to vmax because we place ticks in the middle
+            # (by adding the offset), and would result in the last "tick" being outside the limits
+            stop = vmax + 1 if self.offset == 0 else vmax
+            new_ticks = np.arange(vmin, stop, step)
+            if invert:
+                new_ticks = new_ticks[::-1]
+            return new_ticks + self.offset
 
-    def __call__(self):
-        """Return the locations of the ticks."""
-        vmin, vmax = self.axis.get_view_interval()
-        return self.tick_values(vmin, vmax)
+        def __call__(self):
+            """Return the locations of the ticks."""
+            vmin, vmax = self.axis.get_view_interval()
+            return self.tick_values(vmin, vmax)
+except ImportError:
+    pass