What is the code that converts decimal to octal without using the built-in functions?

What is the code that converts decimal to octal without using the built-in functions

Answer 1

[Elias Gule]

The following code is neither elegant nor memory efficient, but it appears to address your question:

function output = dec2octal(num)
  output = '';

    while num >= 8
        fact    = floor(num / 8);
        num     = mod(num,8);
        output  = [output num2str(fact)]; %#ok<AGROW>
    end

    output = [output num2str(num)];
end

[Walter Roberson]

>= and floor and mod and / and [] and num2str are all built in functions and so cannot be used for this purpose.

[Elias Gule]

I don't think he wanted to take it that far... remember English is not our first language. I think he probably wanted to understand how the decimal to octal logic could be implemented in Matlab.

[miraa basil]

It doesnt give the right answer, it should convert from decimal to octal using your code but the answer doesnt meet.

Answer 2

[Walter Roberson]

https://www.mathworks.com/matlabcentral/answers/38787-what-can-be-programmed-without-any-built-in-functions

[Walter Roberson]

Algorithm:

if input is negative, error

if input is 0, emit '0' and return

initialize output to ''

assign input to a variable

while the variable is greater than 0 do

    take mod8 of the variable
    convert the mod8 to character, and put that at the beginning of the output
    subtract the mod8 from the variable and divide by 8, and assign that result to the variable

end of loop