diff --git a/pymule/plot.py b/pymule/plot.py
index 04ac89f20658db8e264f3de380bd1d67cd4a0d8e..e5cfbf172fab38f9037e1430ae4c476ab459429e 100644
--- a/pymule/plot.py
+++ b/pymule/plot.py
@@ -57,6 +57,15 @@ def kplot(sigma, k, sigmar=[], kr=[],
           labelk="$K$", labelkr=None,
           labelsigma=None, labelsigmar=None):
 
+    if type(sigma) == np.ndarray:
+        sigma = [sigma]
+    if type(sigmar) == np.ndarray:
+        sigmar = [sigmar]
+    if type(k) == np.ndarray:
+        k = [k]
+    if type(kr) == np.ndarray:
+        kr = [kr]
+
     if labelsigma is None:
         labelsigma = r"$\D\sigma\,/\,\D " + labelx + "$"