Plotting section works for one case and not for the other similar case

Any idea why the plotting section of the code is working for the whole "Type == 1" case and not for the whole "Type == 2" case? For the subcases in "Type == 2" that the triangle becomes a line and a point (last two elseif statements) no graphing window appears. It works only if I write plotting sections for each subcase independently "inside" the statements but I want this only once for the whole case.

clc         % Clears the command window
clear all   % Clears the values that are assigned to the variable
close all   % Closes all the graphs

Type = input("Type 1 for hypotenuse or 2 for side : ", 's'); % Asks user if he/she wants to calculate the hypotenuse or the vertical side
Type = str2double(Type);

if Type == 1 % User wants to find hypotenuse
    
    sides = input("Give [side1 side2] = ", 's'); % Asking user to enter the vertical sides' values
    
    sides = str2num(sides); % Use str2num for allowing non-scalars
    
    if numel(sides) == 2 % Make sure that the user enters two numbers for the sides
        
        sides = sides(:).'; % Make sides a row vector
        
        % Assiging easier symbols for the sides
        a = sides(1,1);
        b = sides(1,2);
        
        if any(imag(sides)) ~= true && a >= 0 && b >= 0 || a == 0 && b == 0
           figure(1)
           % x- and y-coordinates of the triangle that will be graphed
           x = [0 a 0 0];
           y = [0 0 b 0];
           plot(x,y)
           title('Pythagorean theorem')
           xlabel('Side 1')
           ylabel('Side 2')
           grid on
       end
        
   if any(imag(sides)) == true || a < 0 || b < 0
       disp('No negative neither complex values for lengths are allowed. Please try again.') % Displays to the user that the lengths cannot be complex neither negative numbers
           
    elseif a > 0 && b > 0
           disp('The hypotenuse is :')
           Hyp = sqrt(a^2 + b^2) % Calculation of the hypotenuse if both sides are given positive
              
    elseif a == 0 && b > 0 || a > 0 && b == 0
           Hyp = sqrt(a^2 + b^2)
           disp('The triangle has become a single straight line') %Displays what happens when only one vertical side is zero
     
    else
           Hyp = sqrt(a^2 + b^2)
           disp('The triangle has become a single point') % Displays what happens when both vertical sides are zero
           plot(x,y,'*')
           grid on
   end
    end
    
elseif Type == 2
    
    sides = input("Give [Hyp side] = ", 's');
    
    sides = str2num(sides); % use str2num for allowing non-scalars
    
    if numel(sides) == 2 % make sure they entered two numbers
        
        sides = sides(:).'; % make sides a row vector
        
        % Assiging easier symbols for the hypotenuse and the sides
        c = sides(1,1);
        b = sides(1,2);
                
        if any(imag(sides)) ~= true && c > 0 && b > 0 && c >= b
           figure(1)
           % x- and y-coordinates of the triangle that will be graphed
           x = [0 sqrt(c^2 - b^2) 0 0];
           y = [0 0 b 0];
           plot(x,y)
           xlabel('Side 1')
           ylabel('Side 2')
           grid on
        end
        
    if any(imag(sides)) == true || c < 0 || b < 0
       disp('No negative neither complex values for lengths are allowed. Please try again') %Displays that the sides cannot be negative neither complex numbers
    
    elseif c > 0 && b > 0 && c > b
       Side = sqrt(c^2 - b^2) %Calculation of the vertical side when the sides are both positive and the hypotenuse is greater than the vertical
       
    elseif c > 0 && b == 0 || c == b && c ~= 0
       Side = sqrt(c^2 - b^2)
       disp('The triangle has become a single straight line') % Displays what happens if the hypotenuse is positive but the side is equal to zero, or if the hypotenuse is equal to the side.
       
    elseif c == 0 && b == 0
        Side = sqrt(c^2 - b^2)
        disp('The triangle has become a single point') % Displays what happens when both the hypotenuse and the side are zero
     
    else
       disp('Hyp must be greater than the side. Please try again.') %Displays what happens when Hyp is less than the vertical side
    end
  end
end

[Cris LaPierre]

It works for me. Can you provide what inputs you use when it doesn't work?

I've modified you code to be able to run case 2 here (i.e. I hardcoded the inputs).

Type = 2;

if Type == 1 % User wants to find hypotenuse
    sides = [3 4]; % Use str2num for allowing non-scalars
    
    if numel(sides) == 2 % Make sure that the user enters two numbers for the sides        
        sides = sides(:).'; % Make sides a row vector
        
        % Assiging easier symbols for the sides
        a = sides(1,1);
        b = sides(1,2);
        
        if any(imag(sides)) ~= true && a >= 0 && b >= 0 || a == 0 && b == 0
           figure(1)
           % x- and y-coordinates of the triangle that will be graphed
           x = [0 a 0 0];
           y = [0 0 b 0];
           plot(x,y)
           title('Pythagorean theorem')
           xlabel('Side 1')
           ylabel('Side 2')
           grid on
       end
        
   if any(imag(sides)) == true || a < 0 || b < 0
       disp('No negative neither complex values for lengths are allowed. Please try again.') % Displays to the user that the lengths cannot be complex neither negative numbers
           
    elseif a > 0 && b > 0
           disp('The hypotenuse is :')
           Hyp = sqrt(a^2 + b^2) % Calculation of the hypotenuse if both sides are given positive
              
    elseif a == 0 && b > 0 || a > 0 && b == 0
           Hyp = sqrt(a^2 + b^2)
           disp('The triangle has become a single straight line') %Displays what happens when only one vertical side is zero
     
    else
           Hyp = sqrt(a^2 + b^2)
           disp('The triangle has become a single point') % Displays what happens when both vertical sides are zero
           plot(x,y,'*')
           grid on
   end
    end
    
elseif Type == 2
    sides = [5 3]; % use str2num for allowing non-scalars
    
    if numel(sides) == 2 % make sure they entered two numbers        
        sides = sides(:).'; % make sides a row vector
        
        % Assiging easier symbols for the hypotenuse and the sides
        c = sides(1,1);
        b = sides(1,2);
                
        if any(imag(sides)) ~= true && c > 0 && b > 0 && c >= b
           figure(1)
           % x- and y-coordinates of the triangle that will be graphed
           x = [0 sqrt(c^2 - b^2) 0 0];
           y = [0 0 b 0];
           plot(x,y)
           xlabel('Side 1')
           ylabel('Side 2')
           grid on
        end
        
    if any(imag(sides)) == true || c < 0 || b < 0
       disp('No negative neither complex values for lengths are allowed. Please try again') %Displays that the sides cannot be negative neither complex numbers
    
    elseif c > 0 && b > 0 && c > b
       Side = sqrt(c^2 - b^2) %Calculation of the vertical side when the sides are both positive and the hypotenuse is greater than the vertical
       
    elseif c > 0 && b == 0 || c == b && c ~= 0
       Side = sqrt(c^2 - b^2)
       disp('The triangle has become a single straight line') % Displays what happens if the hypotenuse is positive but the side is equal to zero, or if the hypotenuse is equal to the side.
       
    elseif c == 0 && b == 0
        Side = sqrt(c^2 - b^2)
        disp('The triangle has become a single point') % Displays what happens when both the hypotenuse and the side are zero
     
    else
       disp('Hyp must be greater than the side. Please try again.') %Displays what happens when Hyp is less than the vertical side
    end
  end
end

Side = 4

[Left Terry]

Please read carefully the text. I said that is not working for the last two elseif statements for the "Type == 2" case. That is, when the user enters a positive non-zero number for the hypotenuse and zero for the side or both the hypotenuse and the side are zero then no graph appears to the screen.

[Voss]

Notice the plot() function only gets called under this condition:

if any(imag(sides)) ~= true && c > 0 && b > 0 && c >= b

You might change it to be more like the condition for the Type == 1 case, if you want to get plots for when b and/or c are 0.

[Left Terry]

Yes. I think I fixed it a liitle:

clc         % Clears the command window
clear all   % Clears the values that are assigned to the variable
close all   % Closes all the graphs

Type = input("Type 1 for hypotenuse or 2 for side : ", 's'); % Asks user if he/she wants to calculate the hypotenuse or one side
Type = str2double(Type);

if Type == 1 % User wants to calculate hypotenuse
    
    sides = input("Give [side1 side2] = ", 's'); % Asking user to enter the perpendicular sides' values
    
    sides = str2num(sides); % Use str2num for allowing non-scalars
    
    if numel(sides) == 2 % Make sure that the user enters two numbers for the sides
        
        sides = sides(:).'; % Make sides a row vector
        
        % Assigning easier symbols for the sides
        a = sides(1,1);
        b = sides(1,2);
 
   if any(imag(sides)) == false && a >= 0 || b >= 0 && a == 0 && b == 0 % Plotting section. Graph appears only for real and non-negative numbers (lengths' values)
           figure(1)
           % x- and y-coordinates of the triangle that will be graphed
           x = [0 a 0 0];
           y = [0 0 b 0];
           
           plot(x,y)
           title('Pythagorean theorem')
           xlabel('Side 1')
           ylabel('Side 2')
           grid on
           if a > b
               axis([0 a 0 a])
           end
           
           if a < b
               axis([0 b 0 b])
           end
  end
               
    if any(imag(sides)) == true || a < 0 || b < 0
       disp('No negative neither complex values for lengths are allowed. Please try again.') % Displays to the user that the lengths cannot be complex neither negative numbers
           
    elseif a > 0 && b > 0
           disp('The hypotenuse is :')
           Hyp = sqrt(a^2 + b^2) % Calculation of the hypotenuse if both sides are given positive
                      
    elseif a == 0 && b == 0
           Hyp = sqrt(a^2 + b^2)
           disp('The triangle has become a single point') % Displays what happens when both vertical sides are zero
           plot(x,y,'*') % Shows the point's location in the graph
           title('Pythagorean theorem')
           xlabel('Side 1')
           ylabel('Side 2')
           grid on
           
    else
        Hyp = sqrt(a^2 + b^2)
        disp('The triangle has become a single straight line') %Displays what happens when only one vertical side is zero
    end
    
    else
        disp('Please try again and enter two numbers for the sides.');
    end
    
elseif Type == 2 % User wants to find
    
    sides = input("Give [Hyp side] = ", 's');
    
    sides = str2num(sides); % Use str2num for allowing non-scalars
    
    if numel(sides) == 2 % Make sure the user entered two numbers
        
        sides = sides(:).'; % Make sides a row vector
        
        % Assigning easier symbols for the hypotenuse and the sides
        c = sides(1,1);
        b = sides(1,2);
                  
        if any(imag(sides)) == false && c >= 0 && b >= 0 && c >= b
           figure(1)
           Side = sqrt(c^2-b^2);

           % x- and y-coordinates of the triangle that will be graphed
           x = [0 Side 0 0];
           y = [0 0 b 0];
                      
           plot(x,y)
           title('Pythagorean theorem')
           xlabel('Side 1')
           ylabel('Side 2')
           grid on
           if b > Side
               axis([0 b 0 b])
           elseif b < Side
               axis([0 Side 0 Side])
           else
               axis([-1 1 -1 1])
           end
           
        end
        
    if any(imag(sides)) == true || c < 0 || b < 0
       disp('No negative neither complex values for lengths are allowed. Please try again') %Displays that the sides cannot be negative neither complex numbers
    
    elseif c == 0 && b == 0
       Side = sqrt(c^2 - b^2)
       disp('The triangle has become a single point') %Displays what happens when both Hyp and vertical are zero
       plot(x,y,'*') % Shows the point's location in the graph
       title('Pythagorean theorem')
       xlabel('Side 1')
       ylabel('Side 2')
       grid on
       
    elseif c > 0 && b > 0 && c > b
       Side = sqrt(c^2 - b^2) %Calculation of the vertical side when the sides are both positive and the hypotenuse is greater than the vertical
    
    elseif c > 0 && b == 0 || c == b
       Side = sqrt(c^2 - b^2)
       disp('The triangle has become a single straight line') % Displays what happens if the hypotenuse is positive but the side is equal to zero, or if the hypotenuse is equal to the side.
       
    else
        disp('Hyp must be greater than the side. Please try again.') %Displays what happens when Hyp is less than the side
    end
    
     else
        disp('Please try again and enter two numbers for the hypotenuse and the side respectively.');
    end
    
else
    disp('Wrong Input. Please try again and type 1 if you want to calculate the hypotenuse or 2 if you want one of the other sides.') % Displays what happens when the user enters a number different than 1 or 2
end

Answer 1

[Cris LaPierre]

The last two else-if statements are working as designed. Perhaps you could more clearly state what "not working" means to you?

The plotting is actually done in the second if-statement for the Type == 2 case. When one or both of your sides are zero, this code is skipped, so no plot command is called. This is because, when, say b=0, then the condition b > 0 is false.

sides = [5 0];
c = sides(1,1);
b = sides(1,2);

any(imag(sides)) ~= true && c > 0 && b > 0 && c >= b

ans = logical
   0

[Left Terry]

Yes, you are right. Thank you very much. My code is almost working. Only in the cases c == 0 && b == 0 in "Type == 1" and a == 0 && b == 0 in "Type == 2" I have to write almost a whole plotting section. That is:

% pyth (Pythagorean Theorem)
clc         % Clears the command window
clear all   % Clears the values that are assigned to the variable
close all   % Closes all the graphs

Type = input("Type 1 for hypotenuse or 2 for side : ", 's'); % Asks user if he/she wants to calculate the hypotenuse or the vertical side
Type = str2double(Type);

if Type == 1 % User wants to find hypotenuse
    
    sides = input("Give [side1 side2] = ", 's'); % Asking user to enter the vertical sides' values
    
    sides = str2num(sides); % Use str2num for allowing non-scalars
    
    if numel(sides) == 2 % Make sure that the user enters two numbers for the sides
        
        sides = sides(:).'; % Make sides a row vector
        
        % Assiging easier symbols for the sides
        a = sides(1,1);
        b = sides(1,2);
 
   if any(imag(sides)) ~= true && a >= 0 && b >= 0
           figure(1)
           % x- and y-coordinates of the triangle that will be graphed
           x = [0 a 0 0];
           y = [0 0 b 0];
           plot(x,y)
           title('Pythagorean theorem')
           xlabel('Side 1')
           ylabel('Side 2')
           grid on
  end
               
    if any(imag(sides)) == true || a < 0 || b < 0
       disp('No negative neither complex values for lengths are allowed. Please try again.') % Displays to the user that the lengths cannot be complex neither negative numbers
           
    elseif a > 0 && b > 0
           disp('The hypotenuse is :')
           Hyp = sqrt(a^2 + b^2) % Calculation of the hypotenuse if both sides are given positive
                      
    elseif a == 0 && b == 0
           Hyp = sqrt(a^2 + b^2)
           disp('The triangle has become a single point') % Displays what happens when both vertical sides are zero
           plot(x,y,'*') % Shows the point's location in the graph
           title('Pythagorean theorem')
           xlabel('Side 1')
           ylabel('Side 2')
           grid on
           
    else
        Hyp = sqrt(a^2 + b^2)
        disp('The triangle has become a single straight line') %Displays what happens when only one vertical side is zero
    end
    
    else
        disp('Please try again and enter two numbers for the sides.');
    end
    
elseif Type == 2
    
    sides = input("Give [Hyp side] = ", 's');
    
    sides = str2num(sides); % use str2num for allowing non-scalars
    
    if numel(sides) == 2 % make sure they entered two numbers
        
        sides = sides(:).'; % make sides a row vector
        
        % Assiging easier symbols for the hypotenuse and the sides
        c = sides(1,1);
        b = sides(1,2);
                  
        if any(imag(sides)) ~= true && c >= 0 && b >= 0 && c >= b
           figure(1)
           % x- and y-coordinates of the triangle that will be graphed
           x = [0 sqrt(c^2 - b^2) 0 0];
           y = [0 0 b 0];
           plot(x,y)
           title('Pythagorean theorem')
           xlabel('Side 1')
           ylabel('Side 2')
           grid on
        end
        
    if any(imag(sides)) == true || c < 0 || b < 0
       disp('No negative neither complex values for lengths are allowed. Please try again') %Displays that the sides cannot be negative neither complex numbers
    
    elseif c == 0 && b == 0
       Side = sqrt(c^2 - b^2)
       disp('The triangle has become a single point') %Displays what happens when both Hyp and vertical are zero
       plot(x,y,'*') % Shows the point's location in the graph
       title('Pythagorean theorem')
       xlabel('Side 1')
       ylabel('Side 2')
       grid on
       
    elseif c > 0 && b > 0 && c > b
       Side = sqrt(c^2 - b^2) %Calculation of the vertical side when the sides are both positive and the hypotenuse is greater than the vertical
    
    elseif c > 0 && b == 0 || c == b
       Side = sqrt(c^2 - b^2)
       disp('The triangle has become a single straight line') % Displays what happens if the hypotenuse is positive but the side is equal to zero, or if the hypotenuse is equal to the side.
       
    else
        disp('Hyp must be greater than the side. Please try again.') %Displays what happens when Hyp is less than the vertical side
    end
    
     else
        disp('Please try again and enter two numbers for the hypotenuse and the side respectively.');
    end
    
else
    disp('Wrong Input. Please try again and type 1 if you want to calculate the hypotenuse or 2 if you want one of the other sides.') % Displays what happens when the user enters a number different than 1 or 2
end

[Cris LaPierre]

There are ways to code this so that you don't have to plot twice, but if this is working for your needs, that's fine, too.

[Left Terry]

Yes, it works. Thank you.