For loop not executing

Hello ,

I am trying to run this for loop and again it stops at section four where it displays letters 'L P E D' but after that it is stuck without any error message.

for i = 1:8

    if i == 1
    j = 'E';
    figure('units','normalized', 'outerposition',[0 0 1 1], 'color', [1 1 1 1])
    axis off
    text(.45, .6, 'E', 'fontname', 'Times', 'fontsize', 200)
    pause 
    LetterOne = input('What letter did you see on the screen?', 's')
    LetterOne = upper(LetterOne)
    return_value =  strcmp(j,LetterOne)
        if return_value == 1,
            disp ' Press a key to continue'
        else return_value == 0,
            disp('Thank you participating in the vision test.')
            disp('Your vision is 20/200');
            break
        end
        clf
    end
        if i == 2
        j = 'F P';
       figure('units','normalized', 'outerposition',[0 0 1 1], 'color', [1 1 1 1])
        axis off
        text(.40, .6, 'F P', 'fontname', 'Times', 'fontsize', 100)
        pause
        LetterTwo = input('What letter did you see on the screen?', 's')
        LetterTwo = upper(LetterTwo)
        return_value =  strcmp(j,LetterTwo)
        if return_value == 1,
            disp ' Press a key to continue'
        else return_value == 0,
            disp('Thank you participating in the vision test.')
            disp('Your vision is 20/100');
            break
        end
        clf
        end

        if i == 3
        j = 'T O Z';
        figure('units','normalized', 'outerposition',[0 0 1 1], 'color', [1 1 1 1])
        axis off
        text(.45, .6, 'T O Z', 'fontname', 'Times', 'fontsize', 70)
        pause
        LetterThree = input('What letter did you see on the screen?', 's')
        LetterThree = upper(LetterThree)
        return_value =  strcmp(j,LetterThree)
        if return_value == 1,
            disp ' Press a key to continue'
        else return_value == 0,
            disp('Thank you participating in the vision test.')
            disp('Your vision is 20/70');
            break
        end
        clf,close
        end

        if i == 4
        j = 'L P E D';
       figure('units','normalized', 'outerposition',[0 0 1 1], 'color', [1 1 1 1])
        axis off
        text(.45, .6, 'L P E D', 'fontname', 'Times', 'fontsize', 50)
        pause
        LetterFour = input('What letter did you see on the screen?', 's')
        LetterFour = upper(LetterFour)
        return_value =  strcmp(j,LetterFour)
        if return_value == 1,
            disp ' Press a key to continue'
        else return_value == 0,
            disp('Thank you participating in the vision test.')
            disp('Your vision is 20/50');
            break
        end
        clf, close
        end

         if i == 5
        j = 'P E C F D';
       figure('units','normalized', 'outerposition',[0 0 1 1], 'color', [1 1 1 1])
        axis off
        text(.35, .6, 'P E C F D', 'fontname', 'Times', 'fontsize', 40)
        pause
        LetterFive = input('What letter did you see on the screen?', 's')
        LetterFive = upper(LetterFive)
        return_value =  strcmp(j,LetterFive)
        if return_value == 1,
            disp ' Press a key to continue'
        else return_value == 0,
            disp('Thank you participating in the vision test.')
            disp('Your vision is 20/40');
            break
        end
        clf, close all
         end

         if i == 6
        j = 'E D P C F Z';
       figure('units','normalized', 'outerposition',[0 0 1 1], 'color', [1 1 1 1])
        axis off
        text(.40, .6, 'E D P C F Z', 'fontname', 'Times', 'fontsize', 30)
        pause
        LetterSix = input('What letter did you see on the screen?', 's')
        LetterSix = upper(LetterSix)
        return_value =  strcmp(j,LetterSix)
        if return_value == 1,
            disp ' Press a key to continue'
        else return_value == 0,
            disp('Thank you participating in the vision test.')
            disp('Your vision is 20/30');
            break
        end
        clf, close
         end

          if i == 7
        j = 'F E L O P Z D';
       figure('units','normalized', 'outerposition',[0 0 1 1], 'color', [1 1 1 1])
        axis off
        text(.45, .55, 'F E L O P Z D', 'fontname', 'Times', 'fontsize', 25)
        pause
        LetterSeven = input('What letter did you see on the screen?', 's')
        LetterSeven = upper(LetterSeven)
        return_value =  strcmp(j,LetterSeven)
        if return_value == 1,
            disp ' Press a key to continue'
        else return_value == 0,
            disp('Thank you participating in the vision test.')
            disp('Your vision is 20/25');
            break
        end
        clf, close
         end

         if i == 8
        j = 'D E F P O T E C';
       figure('units','normalized', 'outerposition',[0 0 1 1], 'color', [1 1 1 1])
        axis off
        text(.45, .6, 'D E F P O T E C', 'fontname', 'Times', 'fontsize', 20)
        pause
        LetterEight = input('What letter did you see on the screen?', 's')
        LetterEight = upper(LetterEight)
        return_value =  strcmp(j,LetterEight)
        if return_value == 1,
            disp ' Press a key to continue'
        else return_value == 0,
            disp('Thank you participating in the vision test.')
            disp('Your vision is 20/20');
            break
        end
        clf, close
         end
         end

Answer 1

[Image Analyst]

We'd have to step through this long program with the debugger, just like you. I think you should be able to do it as well as us. If you don't know how to do it, see this nice tutorial: http://blogs.mathworks.com/videos/2012/07/03/debugging-in-matlab/

Answer 2

[Walter Roberson]

Your "close all" is probably interfering

Instead of using close like that, you should be recording the handle returned from figure() and close() that specific handle.