interp: fix source index computation

1 files changed, 1 insertions, 1 deletions

diff --git a/interp.py b/interp.py
index c57f417..f0f5693 100644
--- a/interp.py
+++ b/interp.py
@@ -1,7 +1,7 @@
 import numpy as np
 
 def interp1d(src_start, src_step, src_val, dst_coords, stencil):
-    idx_src   = (dst_coords / src_step - src_start - (stencil / 2 - 1)).astype(np.int)
+    idx_src   = ((dst_coords - src_start) / src_step - (stencil / 2 - 1)).astype(np.int)
     src_coord = np.linspace(src_start, src_start + src_step * (src_val.shape[0] - 1),
                             src_val.shape[0], dtype = src_val.dtype)