diff --git a/examples/SpectralMethod/Polycrystal/shearZX.yaml b/examples/SpectralMethod/Polycrystal/shearZX.yaml
index 473a82fc7..4395ecf17 100644
--- a/examples/SpectralMethod/Polycrystal/shearZX.yaml
+++ b/examples/SpectralMethod/Polycrystal/shearZX.yaml
@@ -1,7 +1,9 @@
+---
 step:
   - mech:
-      dot_F: [0, 0, 1e-3, 0, 0, 0, 0, 0, 0]
-      P:     [x, x,    x, x, x, x, x, x, x]
+      dot_F: [0, 0, 1e-3,
+              0, 0,    0,
+              0, 0,    0]
     discretization:
       t: 60
       N: 120