Add missing numpy import to pypiezo.wiggle.

diff --git a/pypiezo/wiggle.py b/pypiezo/wiggle.py
index 38942e561c1b3707aeed8de246b2ed5e04209d73..87658e8afb70ecc659304d073c08956fd21f6974 100644 (file)
--- a/pypiezo/wiggle.py
+++ b/pypiezo/wiggle.py
@@ -26,6 +26,8 @@ helping you with your thumbscrews.
 
 import time as _time
 
+import numpy as _numpy
+
 try:
     import h5py as _h5py
     import h5config as _h5config