Checking if a number is non-negative or not?

Many students ask me how do I do this or that in MATLAB.  This is a new addition to the “How do I do that in MATLAB“  series.

In this blog, I show you how to use the if-else-end statement to write a simple program of finding if a number is non-negative or not.

Here are the links for the program.
The mfile is here
The published version of the mfile is here

%% HOW DO I DO THAT IN MATLAB SERIES?
% In this series, I am answering questions that students have asked
%% TOPIC
% How do I check if a number is non-negative or negative
%% SUMMARY
% Language : Matlab 2010a;
% Authors : Autar Kaw and Sri Harsha Garapati;
% Mfile available at
% http://nm.mathforcollege.com/blog/if_else_end_statements_blog.m
% Last Revised : January 23, 2012;
% Abstract: This program shows you how to check if a number is negative or
% non-negative using if-else-end statement in MATLAB
clc
clear all
%% INTRODUCTION

disp(‘ABSTRACT’)
disp(‘   This program shows you how to check if a number is negative or’)
disp(‘   non-negative using if-else-end statement in MATLAB’)
disp(‘ ‘)
disp(‘AUTHOR’)
disp(‘   Autar Kaw and Sri Harsha Garapati of https://autarkaw.wordpress.com’)
disp(‘ ‘)
disp(‘MFILE SOURCE’)
disp(‘   http://nm.mathforcollege.com/blog/if_else_end_statements_blog.m’)
disp(‘ ‘)
disp(‘LAST REVISED’)
disp(‘   February 13, 2012’)
disp(‘ ‘)

%% INPUTS

% Enter the number to be tested
a=4;
%% DISPLAYING INPUTS
disp(‘  ‘)
disp(‘INPUTS’)

% Printing the input number
fprintf(‘The input number to be tested is %g\n’,a)
%% CODE AND DISPLAYING OUTPUT
disp(‘  ‘)
disp(‘OUTPUTS’)

% using the if-else-end statement to check
if (a>=0)
disp(‘The number is nonnegative’)
else
disp(‘The number is negative’)
end

_________________________________________________

This post is brought to you by Holistic Numerical Methods: Numerical Methods for the STEM undergraduate at http://nm.mathforcollege.com, the textbook on Numerical Methods with Applications available from the lulu storefront, the textbook on Introduction to Programming Concepts Using MATLAB, and the YouTube video lectures available at http://nm.mathforcollege.com/videos.  Subscribe to the blog via a reader or email to stay updated with this blog. Let the information follow you.

Author: Autar Kaw

Autar Kaw (http://autarkaw.com) is a Professor of Mechanical Engineering at the University of South Florida. He has been at USF since 1987, the same year in which he received his Ph. D. in Engineering Mechanics from Clemson University. He is a recipient of the 2012 U.S. Professor of the Year Award. With major funding from NSF, he is the principal and managing contributor in developing the multiple award-winning online open courseware for an undergraduate course in Numerical Methods. The OpenCourseWare (nm.MathForCollege.com) annually receives 1,000,000+ page views, 1,000,000+ views of the YouTube audiovisual lectures, and 150,000+ page views at the NumericalMethodsGuy blog. His current research interests include engineering education research methods, adaptive learning, open courseware, massive open online courses, flipped classrooms, and learning strategies. He has written four textbooks and 80 refereed technical papers, and his opinion editorials have appeared in the St. Petersburg Times and Tampa Tribune.