Replacing a part of a matrix in two commands?

I was given a sample question for an exercise today. It goes:

Create the following matrix by typing two commands. Do not type individual elements explicitly.

I started by defining E as a 5x5 matrix of zeros.

E = zeros(5)

This was command 1 but I can't figure out how to replace the given part with consecutive numbers in a single command. I thought of using:

E(3:5,3:5) = ...

but I couldn't figure out what to put on the right hand side.

Answer 1

[Matt J]

It's so hard to know what constitutes a "command" in the opinion of your instructor. The following does it in one line,

E(3:5,3:5)=reshape(1:9,3,3).'

E = 5×5

0 0 0 0 0 0 0 0 0 0 0 0 1 2 3 0 0 4 5 6 0 0 7 8 9

Is this a valid solution just because reshape() is the only function call that does not have its own operator? The transpose is not a command? The subsasgn operation is not a command? The colon operation 1:9 is not a command?

Answer 2

[Matt J]

Maybe as follows?

E(3:5,3:5)=(1:3:7).' + (0:2)

E = 5×5

0 0 0 0 0 0 0 0 0 0 0 0 1 2 3 0 0 4 5 6 0 0 7 8 9