How to use nested for loops?

I am very new to MATLAB, and I have been trying to figure out how to use nested for loops correctly. I want to print out :

    1
    121
    12321
    1234321
    123454321

what should I do if there are a varying number of columns? Any help would be greatly appreciated.

[Walter Roberson]

What have you tried so far?

[Yasmin Touly]

@Walter Roberson, since it is not an array, I am not sure what exactly I should do. I am lost.

[Walter Roberson]

for variable = something : something_else
  for another_variable = thing2 : thing3
     % do something involving variable and another_variable
  end
end

Answer 1

[Birdman]

No need for nested for loops. Try this:

i=1;n=5;
while i<=n
    fprintf('%d',[1:i-1 i:-1:1]);
    fprintf('\n');
    i=i+1;
end

[Walter Roberson]

... This was a homework question. It has come up before as a homework question.

[Birdman]

There is nothing mentioned in the question that it is a homework.

[Yasmin Touly]

@Birdman, But cant i use nested for loops for this?

[Birdman]

Of course you can, but isn't this one simpler?

[Yasmin Touly]

@Birdman, it is, but I wanted to know how I can specifically use nested for loops for this particular question.

[Birdman]

n=5;
for j=1:n
    for i=1:j
    end
    fprintf('%d',[1:i-1 i:-1:1]);
    fprintf('\n');
end