if else nested loops

This is my program... i want the ouput of x and y to be the new values not the 0 and 0. this always returns me 0 and 0 why?

clc
clear
a=input('a')
b=input('b')
x=0;
y=0;
if a>b
    x-1
    y-1
else if a<b
        x+1
        x+2
    else if a==b
            y=1
            x
        end
    end
end
x
y

Answer 1

[A. Sawas]

The problem is not with the if-else statments (although they are not correctly used). You need to assign the new values to x and y like this:

x - 1; % this does not change the values of x
x = x - 1; % the new value (x-1) is assigned to x
y = y - 1;

[A. Sawas]

I guess this is what you are trying to do in a cleaner code:

clc;
clear;
a=input('a');
b=input('b');
x=0;
y=0;
if a>b
    x = x-1;
    y = y-1;
else if a<b
    x = x+1;
    y = y+2;
else % a==b this is the remaining case
    y = 1;
end
disp(x);
disp(y);

[Arouj]

actually this isnt my real code.. i got this and what u r saying is correct but in my real code its giving me zero except for the first case. this is the output

WI =

1.1830

W2 =

0.2196

W1 =

0

W2 =

0.2196

W1=0; W2=0;
if strcmp(RF,'b')
        W1=((abs(Vab))*Iam*cos((angle(Vab)-Iaa)))/1000
        W2=((abs(Vccomp-Vbcomp))*Icm*cos((angle(Vccomp-Vbcomp)-Ica)))/1000
else
if strcmp(RF,'a')
        WI=((abs(Vbcomp-Vacomp))*Ibm*cos((angle(Vbcomp-Vacomp)-Iba)))/1000
         W2=((abs(Vca))*Icm*cos((angle(Vca)-Ica)))/1000
else
if strcmp(RF,'c')
        WI=((abs(Vacomp-Vccomp))*Iam*cos((angle(Vacomp-Vccomp)-Iaa)))/1000
         W2=((abs(Vbc))*Ibm*cos((angle(Vbc)-Iba)))/1000
end 
end
end
W1
W2

[Walter Roberson]

You would need another end on that code, unless you change the else if to elseif

[A. Sawas]

First, to find the issue in the result try to display the value of the variables and intermediate calculations. One easy and quick way is to highlight part of the equation and press F9 to evaluate and see the result.

Second, I suggest you use switch statement which is nicer to follow and code:

switch (RF)
    case 'a'
        % case 'a' code
    case 'b'
        % case 'b' code
    case 'c'
        % case 'c' code
    otherwise
        fprintf('No such case');
end

[Arouj]

i tried this..and got the following output

WI =

1.1830

W2 =

0.2196

W1 =

0

W2 =

0.2196

W1=0;
W2=0;
switch (RF)
    case 'a'
        WI=((abs(-Vab))*Ibm*cos((angle(-Vab)-Iba)))/1000
         W2=((abs(Vca))*Icm*cos((angle(Vca)-Ica)))/1000
         case 'b'
        W1=((abs(Vab))*Iam*cos((angle(Vab)-Iaa)))/1000
        W2=((abs(Vccomp-Vbcomp))*Icm*cos((angle(Vccomp-Vbcomp)-Ica)))/1000
    case 'c'
        WI=((abs(Vacomp-Vccomp))*Iam*cos((angle(Vacomp-Vccomp)-Iaa)))/1000
         W2=(abs(Vbc))*Ibm*cos((angle(Vbc)-Iba))/1000
    otherwise
end
W1
W2

[Image Analyst]

Sawas:

else if a<b

is much, much different than

elseif a<b
    

If you don't know why, just ask.

[A. Sawas]

Image Analyst: Thanks for the note ... I know that very well ;)