Help converting an array to a matrix with 5 columns

I have been working on a script for a while and am towards the tail end of it. I need to convert the array that goes from 1:number to a matrix that has 5 columns. I can't seem to figure out how to do it. If anyone can help me please help out. Here is my code:

% clear
clear
% clc
clc
name=input('Enter name:','s');
% Ask user to input name
number=input('Enter a whole number between 1 and 100:');
% Ask user for a whole number between 1 and 100
while number<1 || number>100 || round(number)~=number
    % a while function that performs actions under if number doesn't meet
    % specifications
    display('Not a valid number please try again');
    number=input('Enter a whole number between 1 and 100:');
end
% End while loop
array=[1:number]
% Create array from 1 to input number
entryposition=0
% Set entry position to 0 for start of loop below
arraylength=length(array)
% Create arraylength variable to help find every multiple of 3
for i = 1:arraylength
    % For loop to make each multiple of 3 negative in final array
    entryposition=(entryposition+1);
    % Cause array to go up by 1 until it meets the input
    if mod(array(entryposition),3)==0;
        % Check for multiples of 3
        array(entryposition)=array(entryposition)*-1;
        % Make 3's negative
    end
end
disp(array)
disp('Thank you!')
disp(name)
% Thank user for running code

[James Tursa]

You could use reshape( ), possibly with a transpose. But what if the number of elements in the array is not a multiple of 5?

Also, you don't need the entryposition variable ... just use the index i directly.

Finally, you might look at the result of array(3:3:end) and that could give you a hint on how to vectorize this code instead of using a loop.

Answer 1

[Vinai Datta Thatiparthi]

Hey James,

From the description you've provided, this could be a possible solution -

(To echo @James' notes, if the variable number is not a multiple of 5, I've used zero-padding)

array = 1:number;
numRows = ceil(number/5);
arrayNew = [array zeros(1, numRows*5 - number)];
reshape(arrayNew, [numRows, 5])

Also, note that the output value of reshape will follow the column-major order.

Hope this helps!