Error: 'N' undefined near line 9 column 13

I don't understand where is the problem of this error. Thanks for help.

[Star Strider]

How are you calling your function?

[João Carvalho]

"senhx" is it?

[Walter Roberson]

When you invoke the function just by commanding

senhx

then where are you expecting it to find a value for N ?

[Robert Henson]

Are you typing the command

senhx

in the Command Window?

Or are you pressing the "Run" button in the editor?

Answer 1

[Steven Lord]

If you try to run this function using the green triangle Run button, that will call this function with no input arguments. But this function requires you to specify its input. You can change this using the procedure described on this documentation page or by typing the function name (with input and output arguments specified) at the prompt in the Command Window.