diff --git a/code/ysolve.f90 b/code/ysolve.f90
index 1792a59..8ab3149 100644
--- a/code/ysolve.f90
+++ b/code/ysolve.f90
@@ -18,6 +18,9 @@
         !First, make sure the right number of inputs have been provided
         IF(COMMAND_ARGUMENT_COUNT().EQ.1)THEN
           CALL GET_COMMAND_ARGUMENT(1,num1char)   !first, read in the two values
+        ELSE IF(COMMAND_ARGUMENT_COUNT().EQ.0)THEN
+          WRITE(*,*)'ERROR, NO COMMAND-LINE ARGUMENT'
+          num1char = "-h"
         ELSE
           WRITE(*,*)'ERROR, TOO MANY COMMAND-LINE ARGUMENTS(MORE THAN ONE). STOPPING'
           STOP