diff --git a/gnuplot/README.md b/gnuplot/README.md
index b85fe8f..a9a43ea 100644
--- a/gnuplot/README.md
+++ b/gnuplot/README.md
@@ -6,7 +6,7 @@
     usage:
       gnuplot line.gp                       run line.gp script
       gnuplot -p line.gp                    run script and kepp figure open
-      gnuplot -e "file='data.dat'; column1=1; column2=2; format='png'; out='line.png'" line.gp
+      gnuplot -e "file='data.dat'; column1=1; column2=2; format='svg'; out='line.svg'" line.gp
                                             run script with altered variables
 
 [line.gp](./line.gp)
diff --git a/gnuplot/README.org b/gnuplot/README.org
index 66b52b4..772a357 100644
--- a/gnuplot/README.org
+++ b/gnuplot/README.org
@@ -3,7 +3,7 @@
   usage:
     gnuplot line.gp                       run line.gp script
     gnuplot -p line.gp                    run script and kepp figure open
-    gnuplot -e "file='data.dat'; column1=1; column2=2; format='png'; out='line.png'" line.gp
+    gnuplot -e "file='data.dat'; column1=1; column2=2; format='svg'; out='line.svg'" line.gp
                                           run script with altered variables
 #+end_src
 
diff --git a/gnuplot/line.gp b/gnuplot/line.gp
index ad3ec47..2733a88 100755
--- a/gnuplot/line.gp
+++ b/gnuplot/line.gp
@@ -1,6 +1,6 @@
 #!/usr/bin/gnuplot
 # usage:
-#   gnuplot -e "file='data.dat'; column1=1; column2=2; format=''; out=''" line.gp
+#   gnuplot -e "file='data.dat'; column1=1; column2=2; format='svg'; out='line.svg'" line.gp
 #
 # format = {'terminal', 'png', 'svg'}