Merge pull request adafruit#20 from kmatch98/master

Corrects off-by-one error in due to rounding errors

Author: tannewt

adafruit_display_shapes/sparkline.py

@@ -139,7 +139,7 @@ def update(self):
             self.y_top = self.y_max
 
         if len(self._spark_list) > 2:
-            xpitch = self.width / (
+            xpitch = (self.width - 1) / (
                 len(self._spark_list) - 1
             )  # this is a float, only make int when plotting the line
 

examples/display_shapes_sparkline_ticks.py

@@ -137,7 +137,7 @@
 
 
 bounding_rectangle = Rect(
-    sparkline1.x, sparkline1.y, chart_width + 1, chart_height + 1, outline=line_color
+    sparkline1.x, sparkline1.y, chart_width, chart_height, outline=line_color
 )
 
 
@@ -160,17 +160,11 @@
 for i in range(total_ticks + 1):
     x_start = sparkline1.x - 5
     x_end = sparkline1.x
-    y_both = sparkline1.y + i * int(round(chart_height / (total_ticks)))
+    y_both = int(round(sparkline1.y + (i * (chart_height) / (total_ticks))))
+    if y_both > sparkline1.y + chart_height - 1:
+        y_both = sparkline1.y + chart_height - 1
     my_group.append(Line(x_start, y_both, x_end, y_both, color=line_color))
-my_group.append(
-    Line(
-        x_start,
-        sparkline1.y + chart_height,
-        x_end,
-        sparkline1.y + chart_height,
-        color=line_color,
-    )
-)
+
 
 # Set the display to show my_group that contains the sparkline and other graphics
 display.show(my_group)