No results from calculations in the command window

Hi there,

For some reason I am not getting any output results in the command window. I click on run and no results appear in the command window from my script. Nor, is there any results in the workspace - even though there a lots of calculations. I have restarted my computer and still there is no change. The last thing I was doing was trying to create a MATLAB function. Also, in the editor tab the option to create a new scipt is faded out. So I can't access a new script. I have been using MATLAB online for months and I have never experienced this problem or any problem like it.

I am very confused and I do not know what is going wrong!

I hope someone can help?

Many thanks,

Scott

Answer 1

[Star Strider]

I am not certain that I fully understasnd your problem.

MATLAB functions have their own workspaces, so variables local to the function will not appear in the workspace window.

I am not certain what you are doing, however be sure to actually call the function (with all appropriate arguments), and return as many outputs as the function produces, at least to troubleshoot this.

[Scott Banks]

Hi Star Strider,

What I am saying is that I click on Run and no results appear in the command window from my script. The command window is just blank - no results from the script are appearing!

[Torsten]

Does it work for other scripts, e.g.

a = 1;
b = 3;
a + b

?

[Scott Banks]

Nope, Torsten, absolutely nothing!

[Star Strider]

Does this work if you run it in the Command Window:

>> a = 1; b = 2; a + b

Running it here produces --

a = 1;  b = 3;  a + b

ans = 4

In MATLAB Online, entering that line at the prompt and then hitting 'ENTER' produces the same result.

.

[Scott Banks]

I just came back to MATLAB after a couple of hours break, and everything was working again until I tried to run my saved function. After trying to run my function its gone back to nothing apearing in the command window.

Yes, even running simple commands in the command window is not working, Star Strider.

[Star Strider]

I'm a bit confused at this point.

What OS are you using and what version of MATLAB?

Does your code only work in MATLAB Online and not in your offline (personal computer) MATLAB installation? (MATLAB Online is currently R2024b Update 5. I just now checked.)

if so, uninstalling and reinstalling MATLAB may be yoiur only option.

[Scott Banks]

I think I have found the problem:

In my function I have an option to select certain data. Here is the complete file.

function [Inflex] = inflection_point

Inflex01 = [-0.35;-0.10;0.10;0.30;0.50;0.75;1.20];
Inflex02 = [-0.50;0.15;0.25;0.35;0.45;0.60;0.95];
Inflex03 = [0.10;0.25;0.30;0.40;0.45;0.55;0.85];
Inflex04 = [0.20;0.30;0.35;0.40;0.45;0.50;0.80];
Inflex05 = [0.20;0.35;0.40;0.40;0.45;0.50;0.75];
Inflex06 = [0.25;0.35;0.40;0.45;0.45;0.50;0.70];
Inflex07 = [0.30;0.35;0.40;0.45;0.45;0.50;0.70];
Inflex08 = [0.30;0.40;0.45;0.45;0.45;0.50;0.65];
Inflex09 = [0.35;0.40;0.40;0.45;0.45;0.50;0.65];
Inflex1 = [0.35;0.40;0.40;0.45;0.45;0.50;0.65];
Inflex2 = [0.40;0.45;0.45;0.50;0.50;0.50;0.55];
Inflex3 = [0.45;0.45;0.45;0.50;0.50;0.50;0.55];
Inflex4 = [0.40;0.50;0.50;0.50;0.50;0.50;0.55];
Inflex5 = [0.40;0.50;0.50;0.50;0.50;0.50;0.55];

Storey = ['7';'6';'5';'4';'3';'2';'1'];
Khat01 = [Inflex01];
Khat02 = [Inflex02];
Khat03 = [Inflex03];
Khat04 = [Inflex04];
Khat05 = [Inflex05];
Khat06 = [Inflex06];
Khat07 = [Inflex07];
Khat08 = [Inflex08];
Khat09 = [Inflex09];
Khat1 = [Inflex1];
Khat2 = [Inflex2];
Khat3 = [Inflex3];
Khat4 = [Inflex4];
Khat5 = [Inflex5];

Tb = table(Storey,Khat01,Khat02,Khat03,Khat04,Khat05,Khat06,Khat07,Khat08,Khat09,Khat1,Khat2,Khat3,Khat4,Khat5)


Khat = input('Enter a value of Khat: ')
      
switch Khat
    case (Khat >= 0) && (Khat <= 0.14)
        disp(Tb(:,2))
    case 0.2
        disp(Tb(:,3))
    case 0.3
        disp(Tb(:,4))
    case 0.4
        disp(Tb(:,5))
    case 0.5
        disp(Tb(:,6))
    case 0.6
        disp(Tb(:,7))
    case 0.7
        disp(Tb(:,8))
    case 0.8
        disp(Tb(:,9))
    case 0.9
        disp(Tb(:,10))
    case 1
        disp(Tb(:,11))
    case 2
        disp(Tb(:,12))
    case 3
        disp(Tb(:,13))
    case 4
        disp(Tb(:,14))
    case 5
        disp(Tb(:,15))
end
end

Now, when I am in a different file and run this the command window like I said goes blank. However, if I enter say 0.8 in the command window I get the correct display.

Which is great!!!

The only annoying thing is that I don't get the message "Enter a value of Khat", like I do in the file for the inflection_point itself. The command window is empty with no prompt to input a value of Khat. Do you know why this is?

[Star Strider]

When I put your function in a script file that includes the command:

inflection_point

regardless of the number I supply in response to the prompt (that always shows up), I get:

Output argument "Inflex" (and possibly others) not assigned a value in the execution ...

You need to assign a value to 'Inflex' at an appropriate point in your code.

I'm not certain what your function actually is supposed to do, however using the ismember (or ismembertol) function or one of the interpolation functions might be appropriate in order to asssign a value to 'Inflex'. I can probably help with that if I know what you actually want to do.

The code I'm using (in its entirety) is:

% % % Scott_Banks_2025_07_22.m

Infles = inflection_point

function [Inflex] = inflection_point

Inflex01 = [-0.35;-0.10;0.10;0.30;0.50;0.75;1.20];

Inflex02 = [-0.50;0.15;0.25;0.35;0.45;0.60;0.95];

Inflex03 = [0.10;0.25;0.30;0.40;0.45;0.55;0.85];

Inflex04 = [0.20;0.30;0.35;0.40;0.45;0.50;0.80];

Inflex05 = [0.20;0.35;0.40;0.40;0.45;0.50;0.75];

Inflex06 = [0.25;0.35;0.40;0.45;0.45;0.50;0.70];

Inflex07 = [0.30;0.35;0.40;0.45;0.45;0.50;0.70];

Inflex08 = [0.30;0.40;0.45;0.45;0.45;0.50;0.65];

Inflex09 = [0.35;0.40;0.40;0.45;0.45;0.50;0.65];

Inflex1 = [0.35;0.40;0.40;0.45;0.45;0.50;0.65];

Inflex2 = [0.40;0.45;0.45;0.50;0.50;0.50;0.55];

Inflex3 = [0.45;0.45;0.45;0.50;0.50;0.50;0.55];

Inflex4 = [0.40;0.50;0.50;0.50;0.50;0.50;0.55];

Inflex5 = [0.40;0.50;0.50;0.50;0.50;0.50;0.55];

Storey = ['7';'6';'5';'4';'3';'2';'1'];

Khat01 = [Inflex01];

Khat02 = [Inflex02];

Khat03 = [Inflex03];

Khat04 = [Inflex04];

Khat05 = [Inflex05];

Khat06 = [Inflex06];

Khat07 = [Inflex07];

Khat08 = [Inflex08];

Khat09 = [Inflex09];

Khat1 = [Inflex1];

Khat2 = [Inflex2];

Khat3 = [Inflex3];

Khat4 = [Inflex4];

Khat5 = [Inflex5];

Tb = table(Storey,Khat01,Khat02,Khat03,Khat04,Khat05,Khat06,Khat07,Khat08,Khat09,Khat1,Khat2,Khat3,Khat4,Khat5)

Khat = input('Enter a value of Khat: ')

switch Khat

case (Khat >= 0) && (Khat <= 0.14)

disp(Tb(:,2))

case 0.2

disp(Tb(:,3))

case 0.3

disp(Tb(:,4))

case 0.4

disp(Tb(:,5))

case 0.5

disp(Tb(:,6))

case 0.6

disp(Tb(:,7))

case 0.7

disp(Tb(:,8))

case 0.8

disp(Tb(:,9))

case 0.9

disp(Tb(:,10))

case 1

disp(Tb(:,11))

case 2

disp(Tb(:,12))

case 3

disp(Tb(:,13))

case 4

disp(Tb(:,14))

case 5

disp(Tb(:,15))

end

end

% ========================================================================

.

EDIT -- Corrected typographical errors.

.

[Star Strider]

Considering Help with Inequalities In Switch Statement are you still interested in pursuing this here?

I offered to help with respect to using various functions, depending on what you want to do (that I'm still not certain about). You could use any of several functions to determine what values(s) 'Inflex' is everntually assigned.

.

[Scott Banks]

Thanks, Star Strider. I have now assigned a value to Inflex and all seems to be good now.

It quite long winded what I want to do, but I want to be able to extract any inflection point that is contained in the Table Tb and apply it to any column in a storey within a tall building (there's a much bigger picture here). Note: an inflection point in structural engineering is a point where the bending moment equals zero in the member.

Khat is a parameter that takes the mean stiffness of beams relative to the column stiffness. If Khat equals 0.6 for example, then the coresponding inflection points are found in the 7th column in the table Tb - for each of the 7 storeys. Thus, if I want to work on the 7th storey with Khat equaling 0.6, the percentage distance for the inflection point from the bottom of the storey is 25% (0.25 in the table). So you multiply the length of the column by 0.25, there you have the zero point bending moment.

Thus, again, I want to be able to extract any value from the table when I need to. There is still some way to go, so I will likely be asking for more help!

[Star Strider]

My pleasure.

I'm not certain what the variables in the table represent.

Do you want to interpolate between them to get a single value or interpolated vector for 'Inflex', or do you want to get the closest column to a specific value for 'Khat' to assign to 'Inflex'?

Here's an example of an interpolation approach --

Inflex = inflection_point

Tb = 7×15 table
    Storey    Khat01    Khat02    Khat03    Khat04    Khat05    Khat06    Khat07    Khat08    Khat09    Khat1    Khat2    Khat3    Khat4    Khat5
    ______    ______    ______    ______    ______    ______    ______    ______    ______    ______    _____    _____    _____    _____    _____

      7       -0.35      -0.5       0.1       0.2       0.2      0.25       0.3       0.3      0.35     0.35      0.4     0.45      0.4      0.4 
      6        -0.1      0.15      0.25       0.3      0.35      0.35      0.35       0.4       0.4      0.4     0.45     0.45      0.5      0.5 
      5         0.1      0.25       0.3      0.35       0.4       0.4       0.4      0.45       0.4      0.4     0.45     0.45      0.5      0.5 
      4         0.3      0.35       0.4       0.4       0.4      0.45      0.45      0.45      0.45     0.45      0.5      0.5      0.5      0.5 
      3         0.5      0.45      0.45      0.45      0.45      0.45      0.45      0.45      0.45     0.45      0.5      0.5      0.5      0.5 
      2        0.75       0.6      0.55       0.5       0.5       0.5       0.5       0.5       0.5      0.5      0.5      0.5      0.5      0.5 
      1         1.2      0.95      0.85       0.8      0.75       0.7       0.7      0.65      0.65     0.65     0.55     0.55     0.55     0.55 

Khat = 0.4200

Inflex = 7×2 table
    Storey    Interpolated Value for Khat = 0.4200
    ______    ____________________________________

      7                        0.2                
      6                       0.31                
      5                       0.36                
      4                        0.4                
      3                       0.45                
      2                        0.5                
      1                       0.79                

function [Inflex] = inflection_point
Inflex01 = [-0.35;-0.10;0.10;0.30;0.50;0.75;1.20];
Inflex02 = [-0.50;0.15;0.25;0.35;0.45;0.60;0.95];
Inflex03 = [0.10;0.25;0.30;0.40;0.45;0.55;0.85];
Inflex04 = [0.20;0.30;0.35;0.40;0.45;0.50;0.80];
Inflex05 = [0.20;0.35;0.40;0.40;0.45;0.50;0.75];
Inflex06 = [0.25;0.35;0.40;0.45;0.45;0.50;0.70];
Inflex07 = [0.30;0.35;0.40;0.45;0.45;0.50;0.70];
Inflex08 = [0.30;0.40;0.45;0.45;0.45;0.50;0.65];
Inflex09 = [0.35;0.40;0.40;0.45;0.45;0.50;0.65];
Inflex1 = [0.35;0.40;0.40;0.45;0.45;0.50;0.65];
Inflex2 = [0.40;0.45;0.45;0.50;0.50;0.50;0.55];
Inflex3 = [0.45;0.45;0.45;0.50;0.50;0.50;0.55];
Inflex4 = [0.40;0.50;0.50;0.50;0.50;0.50;0.55];
Inflex5 = [0.40;0.50;0.50;0.50;0.50;0.50;0.55];
Storey = ['7';'6';'5';'4';'3';'2';'1'];
Khat01 = [Inflex01];
Khat02 = [Inflex02];
Khat03 = [Inflex03];
Khat04 = [Inflex04];
Khat05 = [Inflex05];
Khat06 = [Inflex06];
Khat07 = [Inflex07];
Khat08 = [Inflex08];
Khat09 = [Inflex09];
Khat1 = [Inflex1];
Khat2 = [Inflex2];
Khat3 = [Inflex3];
Khat4 = [Inflex4];
Khat5 = [Inflex5];
Tb = table(Storey,Khat01,Khat02,Khat03,Khat04,Khat05,Khat06,Khat07,Khat08,Khat09,Khat1,Khat2,Khat3,Khat4,Khat5)

% Khat = input('Enter a value of Khat: ')

Khat = 0.42

Tba = [Tb{:,2} table2array(Tb(:,2:end))];
ival = [0 0.14 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 2 3 4 5];

inflx = interp1(ival.', Tba.', Khat);
Inflex = table(Storey,inflx(:), VariableNames={'Storey',sprintf('Interpolated Value for Khat = %.4f',Khat)});

% switch Khat
%     case (Khat >= 0) && (Khat <= 0.14)
%         disp(Tb(:,2))
%     case 0.2
%         disp(Tb(:,3))
%     case 0.3
%         disp(Tb(:,4))
%     case 0.4
%         disp(Tb(:,5))
%     case 0.5
%         disp(Tb(:,6))
%     case 0.6
%         disp(Tb(:,7))
%     case 0.7
%         disp(Tb(:,8))
%     case 0.8
%         disp(Tb(:,9))
%     case 0.9
%         disp(Tb(:,10))
%     case 1
%         disp(Tb(:,11))
%     case 2
%         disp(Tb(:,12))
%     case 3
%         disp(Tb(:,13))
%     case 4
%         disp(Tb(:,14))
%     case 5
%         disp(Tb(:,15))
% end
end

The online 'Run' facility doesn't permit any interactivity, so I defined 'Khat' internally here.

EDIT -- (22 Jul 2025 at 21:37)

Added 'interpolation approach'.

.

[Scott Banks]

That's brilliant, Star Strider. I was just going to go for the closet column for a single value, If I would have used interpolation I would have probably tried to incorporate the formula - y = y1 + (x - x1)/(x2 - x1)*(y2 - y1). Which would have had much more code. Great one!

[Star Strider]

My pleasure!

If my Answer helped you solve your problem, please Accept it!

.

EDIT -- (23 Jul 2025 at 00:55)

Note that there are also stepwise interpolation methods available, notably 'previous', 'next', and 'nearest'.

.