< M A T L A B (R) > Copyright 1984-2018 The MathWorks, Inc. R2018a (9.4.0.813654) 64-bit (glnxa64) February 23, 2018 To get started, type one of these: helpwin, helpdesk, or demo. For product information, visit www.mathworks.com. >> test_script f1: error: Error using f1 (line 3) Error: "sigma" was previously used as a variable, conflicting with its use here as the name of a function or command. See "How MATLAB Recognizes Command Syntax" in the MATLAB documentation for details. f1 (): none f1a (): none f2: error: Error using f2 (line 3) Error: "sigma" was previously used as a variable, conflicting with its use here as the name of a function or command. See "How MATLAB Recognizes Command Syntax" in the MATLAB documentation for details. f2 (): none f2a (): none f3 (): command f3a (): function f3 (1): command f3a (1): none f4 (): command f4a (): function