diff --git a/example/rcnn/rcnn/dataset/pascal_voc_eval.py b/example/rcnn/rcnn/dataset/pascal_voc_eval.py
index <HASH>..<HASH> 100644
--- a/example/rcnn/rcnn/dataset/pascal_voc_eval.py
+++ b/example/rcnn/rcnn/dataset/pascal_voc_eval.py
@@ -48,8 +48,8 @@ def voc_ap(rec, prec, use_07_metric=False):
             ap += p / 11.
     else:
         # append sentinel values at both ends
-        mrec = np.concatenate([0.], rec, [1.])
-        mpre = np.concatenate([0.], prec, [0.])
+        mrec = np.concatenate(([0.], rec, [1.]))
+        mpre = np.concatenate(([0.], prec, [0.]))
 
         # compute precision integration ladder
         for i in range(mpre.size - 1, 0, -1):
Fix voc_ap issue in rcnn test path. (#<I>)

* Fixes mxnet additonal deps: python-matplotlib is an apt package, not a pip package, and the pip package for scimage is scikit-image



* Fixes issue in voc_ap where np.concatenate expects a tuple.