# Strange outputs when using disp or fprintf

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Alexander Babayi on 3 Oct 2016
Commented: Stephen23 on 3 Oct 2016
I currently have a code with which you input 2 numbers (x and y) and two outputs should come up (th and r). I'm having some trouble getting matlab to actually display those two outputs in the command window. Although the correct values for those outputs are listed in the workspace, my code doesn't seem to be able to reproduce those two outputs. Here is the code:
prompt = 'Enter x value';
x = input(prompt)
prompt = 'Enter y value';
y = input(prompt)
r = sqrt(x.^2 + y.^2);
if x>0;
t = atan(y/x);
elseif x<0, y>0;
t = atan(y/x)+pi;
elseif x<0, y<0;
t = atan(y/x)-pi;
elseif x<0, y==0;
t = pi;
elseif x==0, y>0;
t = pi/2;
elseif x==0, y<0;
t = -pi/2;
elseif x==0, y==0;
t = 0;
end
fprintf('r = %s', r);
fprintf('theta = %s degrees', th);
The "r" output value displayed in the command window, for some reason, gives me a box symbol. The "th" output value displayed in the command window gives me a "Z". I'm not sure how it is displaying these outputs, as the correct ones are in the workspace. Maybe the part of the code that is meant to print them in the command box is faulty?
Thank you.
Steven Lord on 3 Oct 2016
In addition to what Walter said, this line of code won't do what you want.
elseif x<0, y>0;
To combine multiple conditions in an if statement you need to combine them with and or or.
Alexander Babayi on 3 Oct 2016
Thank you, I was actually just testing it and wondering why it wasn't working the way I intended. I used "&&" to combine the two conditions, if that also works. It seems to have worked.

Walter Roberson on 3 Oct 2016
Don't use %s for numeric values. %s is for strings. Use %f or %e or %g for numeric values.
Alexander Babayi on 3 Oct 2016
Thank you, I didn't realize that.
Stephen23 on 3 Oct 2016
@Alexander Babayi: you don't need to guess how MATLAB works (e.g. what fprintf format string to use), you could try reading the documentation: