How can I override a value with an input?

10 views (last 30 days)
I have a list of variables with values, but I want to be able to override one of those values with an input. To demonstrate:
function [output] = test(variable, value)
x = 2;
y = 3;
q = 10;
And let's say my input is (x, 5). Other than using a bunch of if statements, is there a way to make x = 5?
Andrew on 8 Aug 2014
That's the thing, I don't know how to use them. 'variable' should match one of the ones declared in the code (i.e. x, y, or q) and 'value' is whatever value that variable should be. So if my input is (y, 10), then I want to set y = 10.
I'm explaining this poorly, I apologize, but I'm not quite sure how else to describe it.

Sign in to comment.

Accepted Answer

A Jenkins
A Jenkins on 8 Aug 2014
Some of it depends on how much you want to protect against "bad" values or variable names being passed. But here is a simple trick:
function [output] = test(variable, value)
mydata.x = 2;
mydata.y = 3;
mydata.q = 10;
>> test('x',5)
mydata =
x: 5
y: 3
q: 10

More Answers (1)

Geoff Hayes
Geoff Hayes on 8 Aug 2014
Could also just compare the input variable to a set of pre-defined "matches"
function [output] = test(variable, value)
x = 2;
y = 3;
q = 10;
if ischar(variable) && isvector(variable)
if strcmp(variable,'x')
x = value;
elseif strcmp(variable,'y')
y = value;
elseif strcmp(variable,'q')
q = value;
The above will guard against the case where variable is not a string, and is one of x, y, and q.


Find more on Startup and Shutdown in Help Center and File Exchange

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by