From 37a0a8eb8ca109026c3c13b4fa6c976382c38ccb Mon Sep 17 00:00:00 2001
From: Joseph Crail <jbcrail@gmail.com>
Date: Thu, 27 Apr 2017 18:14:24 -0400
Subject: [PATCH] Adjust line to account for exclusive upper bounds

When extending a line, I decremented the upper bounds for both x and y.

Fix #328
---
 datashader/glyphs.py            |  3 +++
 datashader/tests/test_dask.py   |  2 +-
 datashader/tests/test_glyphs.py | 10 +++++-----
 datashader/tests/test_pandas.py |  2 +-
 4 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/datashader/glyphs.py b/datashader/glyphs.py
index 97c3f6794..321cc3cf7 100644
--- a/datashader/glyphs.py
+++ b/datashader/glyphs.py
@@ -179,6 +179,9 @@ def extend_line(vt, bounds, xs, ys, plot_start, *aggs_and_cols):
         """Aggregate along a line formed by ``xs`` and ``ys``"""
         sx, tx, sy, ty = vt
         xmin, xmax, ymin, ymax = bounds
+        # Adjustments for exclusive upper bounds for x and y
+        xmax -= 1
+        ymax -= 1
         nrows = xs.shape[0]
         i = 0
         while i < nrows - 1:
diff --git a/datashader/tests/test_dask.py b/datashader/tests/test_dask.py
index 90e88c417..c37254c74 100644
--- a/datashader/tests/test_dask.py
+++ b/datashader/tests/test_dask.py
@@ -179,7 +179,7 @@ def test_line():
                     [0, 1, 0, 0, 0, 1, 0],
                     [1, 0, 0, 0, 0, 0, 1],
                     [0, 0, 0, 0, 0, 0, 0],
-                    [3, 0, 0, 0, 0, 0, 1],
+                    [1, 0, 0, 0, 0, 0, 1],
                     [0, 2, 0, 0, 0, 1, 0],
                     [0, 0, 1, 0, 1, 0, 0]], dtype='i4')
     out = xr.DataArray(sol, coords=[np.arange(-3., 4.), np.arange(-3., 4.)],
diff --git a/datashader/tests/test_glyphs.py b/datashader/tests/test_glyphs.py
index b1a70c1a0..8d5256e5c 100644
--- a/datashader/tests/test_glyphs.py
+++ b/datashader/tests/test_glyphs.py
@@ -128,7 +128,7 @@ def test_extend_lines():
                     [0, 0, 0, 0, 0],
                     [0, 1, 1, 1, 0],
                     [0, 1, 0, 1, 0],
-                    [0, 1, 0, 1, 0]])
+                    [0, 0, 0, 0, 0]])
     agg = new_agg()
     extend_line(vt, bounds, xs, ys, False, agg)
     np.testing.assert_equal(agg, out)
@@ -141,10 +141,10 @@ def test_extend_lines():
     xs = np.array([2, 1, 0, -1, -4, -1, -100, -1, 2])
     ys = np.array([-1, -2, -3, -4, -1, 2, 100, 2, -1])
     out = np.array([[0, 1, 0, 1, 0],
-                    [1, 0, 0, 0, 1],
+                    [1, 0, 0, 0, 0],
                     [0, 0, 0, 0, 0],
-                    [1, 0, 0, 0, 1],
-                    [0, 1, 0, 1, 0]])
+                    [1, 0, 0, 0, 0],
+                    [0, 0, 0, 0, 0]])
     agg = new_agg()
     extend_line(vt, bounds, xs, ys, True, agg)
     np.testing.assert_equal(agg, out)
@@ -163,5 +163,5 @@ def test_extend_lines_nan():
     ys = np.array([-3, -2, np.nan, 0, 1])
     agg = new_agg()
     extend_line(vt, bounds, xs, ys, True, agg)
-    out = np.diag([1, 1, 0, 1, 1])
+    out = np.diag([1, 1, 0, 1, 0])
     np.testing.assert_equal(agg, out)
diff --git a/datashader/tests/test_pandas.py b/datashader/tests/test_pandas.py
index 3fa20dbbf..49706af33 100644
--- a/datashader/tests/test_pandas.py
+++ b/datashader/tests/test_pandas.py
@@ -172,7 +172,7 @@ def test_line():
                     [0, 1, 0, 0, 0, 1, 0],
                     [1, 0, 0, 0, 0, 0, 1],
                     [0, 0, 0, 0, 0, 0, 0],
-                    [3, 0, 0, 0, 0, 0, 1],
+                    [1, 0, 0, 0, 0, 0, 1],
                     [0, 2, 0, 0, 0, 1, 0],
                     [0, 0, 1, 0, 1, 0, 0]], dtype='i4')
     out = xr.DataArray(sol, coords=[np.arange(-3., 4.), np.arange(-3., 4.)],