Triangular Multiplication Table - matlab

Question

I'm working on a program that's supposed to write out the multiplication table as shown in the picture.
This is what I've done
A = (1:10)'*(1:10);
tril (A)
And this is my output. Is there a way I can do this without the zeros?
Or should I go with a different approach? Any help is greatly appreciated.
1 0 0 0 0 0 0 0 0 0
2 4 0 0 0 0 0 0 0 0
3 6 9 0 0 0 0 0 0 0
4 8 12 16 0 0 0 0 0 0
5 10 15 20 25 0 0 0 0 0
6 12 18 24 30 36 0 0 0 0
7 14 21 28 35 42 49 0 0 0
8 16 24 32 40 48 56 64 0 0
9 18 27 36 45 54 63 72 81 0
10 20 30 40 50 60 70 80 90 100

Answer 1

Here's one way:
A=tril((1:10)'*(1:10))
A(A==0)=NaN;
S=num2str(A);
S(S==78|S==97)=' '
The second line distinguishes plain old '0' from a pesky '0' in, say, '20'.
The third line converts the array to a string.
The last line replaces capital 'N' (character 78) and lowercase 'a' (character 97) with blank space.

Answer 2

Your approach is good, but if you want to avoid the zeros you want strings, not numbers. For example,
>> n = 10;
>> char(arrayfun(#(k) {sprintf('%i ', k:k:k^2)}, 1:n).')
ans =
1
2 4
3 6 9
4 8 12 16
5 10 15 20 25
6 12 18 24 30 36
7 14 21 28 35 42 49
8 16 24 32 40 48 56 64
9 18 27 36 45 54 63 72 81
10 20 30 40 50 60 70 80 90 100
How it works
sprintf('%i ', k:k:k^2) generates each row of the table as a string. cellfun is used to iterate over all rows. The rows are packed into a cell array of strings, and that cell array is converted to a char matrix, which automatically pads with spaces.