Using switch case with multiple variables (instead of just n, with n1, n2, etc.).

Hello all,

I'm trying to find a way to run the following code:

x1=4;
x2=4;
y1=4;
y2=4;
switch x1,x2,y1,y2
    case x1>0 && y1<0 && ((y2>0) || (y2<0 && x2<0) || (x2>0 && y2<y1))
        disp('Subtract from 360')
    otherwise 
        disp('Keep as is')
end

and I get this error:

Error: File: untitled5.m Line: 5 Column: 11
Invalid expression. Check for missing multiplication operator, missing or unbalanced delimiters, or
other syntax error. To construct matrices, use brackets instead of parentheses.

I'm not sure if I can use switch case with mutliple variables like that. I'd appreciate it if anyone could lend me hand about this.

Answer 1

[Cris LaPierre]

You can only switch on one variable. Try this instead

x1=4;
x2=4;
y1=-4;
y2=4;
switch true
    case x1>0 && y1<0 && (y2>0 || y2<0 && x2<0 || x2>0 && y2<y1)
        disp('Subtract from 360')
    otherwise 
        disp('Keep as is')
end

[Arian Kolahi Sohrabi]

Wow. Thank you so much.

Quick question: how did you know "true" could be used there like that?

[Steven Lord]

Or as an even easier approach:

x1=4;
x2=4;
y1=-4;
y2=4;
if x1>0 && y1<0 && (y2>0 || y2<0 && x2<0 || x2>0 && y2<y1)
    disp('Subtract from 360')
else
    disp('Keep as is')
end

If you need to add more conditions, add elseif blocks inside the if block, before the else keyword.

Alternately, since this looks like you're using x and y coordinates to generate an angle, the atan2d function may be of use to you.