diff --git a/peyote/sampler.py b/peyote/sampler.py
index 8cd16c4bcc23fcdddaab4b0c56ffdc744b135da7..fb62b68da3f23d974168cc9591f873ab0a5772c0 100644
--- a/peyote/sampler.py
+++ b/peyote/sampler.py
@@ -72,6 +72,8 @@ class Sampler:
         self.outdir = outdir
         self.kwargs = kwargs
 
+        self.ndim = 0
+
         self.sampler_string = sampler_string
         self.import_external_sampler()