remainder while dividing a number by x number of digits

if i have a line of code like this

while(rem(i,2) ~= 0 || rem(i,3) ~= 0 || rem(i,4) ~= 0

its OK if I know the limit of 'i' , what can I do to make i open ended such that I can input 'i' as any number and the while loop will be performed . E.G i = 30 , the the while loop continues up to 'rem(1,4)~=0'

[Stephen23]

This code

 while(rem(i,2) ~= 0 rem(i,3) ~= 0 rem(i,4) ~= 0

is not valid MATLAB syntax (it is missing a parenthesei). It also seems likely that you want these logical equivalence operators to be joined by OR or AND operators, but you would need to tell us which.

[OLUBUKOLA ogunsola]

yes, there is in between its in the for while(rem(i,2) ~= 0 ||rem(i,3) ~= 0 ||rem(i,4) ~= 0

[Guillaume]

Olubukola, bars, |, in posts have special meaning (they format text like this) Therefore, even though you wrote them they did not appear.

If you format your code as code by pressing the {}Code button above the post, then they'll show up as intended.

Answer 1

[Guillaume]

Avoid using i as a variable name, it's meaningless and it's also a function in matlab.

To answer your question, use vectorised operations with any:

numdigits = 30; %your limit
value = 150; %your i
%test value against all numbers between 1 all at once (use array 1:numdigits)
%if ANY of the remainder is not 0, do something
while any(rem(value, 2:numdigits))
   %do something
end

[OLUBUKOLA ogunsola]

@Guillaume , i'm sorry I don't understand where 'value=150' fits in . this is the code i'm trying to adjust to fit what i'm trying to achieve

while(rem(i,2) ~= 0 || rem(i,3) ~= 0 || rem(i,4) ~= 0 || ...
        rem(i,5) ~= 0 || rem(i,6) ~=0 || rem(i,7) ~= 0 || rem(i,8) ~= 0 ...
         || rem(i,9) ~= 0 || rem(i,10) ~= 0 || rem(i,11) ~= 0 ...
          || rem(i,12) ~= 0  || rem(i,13) ~= 0  || rem(i,14) ~= 0 ...
           || rem(i,15) ~= 0 || rem(i,16) ~= 0 || rem(i,17) ~= 0 ...
            || rem(i,18) ~= 0 || rem(i,19) ~= 0 || rem(i,20) ~= 0)
        i = i+20;

in my own code i want the user to determine where we will stop, not like in this case where it is 20.

[Guillaume]

value is the variable you've called i, I just gave it a better name.

Your code is equivalent to:

while any(rem(i, 2:20))
   i = i + 20;

rem(i, 2:20) will result in a vector of the remainders of i divided by the integers 2 to 20. any on that vector will be true if any of then is not zero.

But please, use a better variable name than i.