diff --git a/examples/mayavi/interactive/coil_design_application.py b/examples/mayavi/interactive/coil_design_application.py
index 4172ea42e..09e7ee7ae 100644
--- a/examples/mayavi/interactive/coil_design_application.py
+++ b/examples/mayavi/interactive/coil_design_application.py
@@ -185,10 +185,10 @@ def _get_Bnorm(self):
         # to use an ImageData
         Bmax = 10 * np.median(Bnorm)
 
-        Bx[Bnorm > Bmax] = np.NAN
-        By[Bnorm > Bmax] = np.NAN
-        Bz[Bnorm > Bmax] = np.NAN
-        Bnorm[Bnorm > Bmax] = np.NAN
+        Bx[Bnorm > Bmax] = np.nan
+        By[Bnorm > Bmax] = np.nan
+        Bz[Bnorm > Bmax] = np.nan
+        Bnorm[Bnorm > Bmax] = np.nan
 
         self.Bx = Bx
         self.By = By