% (modulo)
% (modulo)
Description
Calculates the remainder when one integer is divided by another. It is useful for keeping a variable within a particular range (e.g. the size of an array).
Syntax
result = dividend % divisor
Parameters
dividend: the number to be divided
divisor: the number to divide by
Returns
the remainder
Examples
x = 7 % 5; // x now contains 2 x = 9 % 5; // x now contains 4 x = 5 % 5; // x now contains 0 x = 4 % 5; // x now contains 4
Example Code
/* update one value in an array each time through a loop */ int values[10]; int i = 0; void setup() {} void loop() { values[i] = analogRead(0); i = (i + 1) % 10; // modulo operator rolls over variable }
Tip
The modulo operator does not work on floats.
See also
Corrections, suggestions, and new documentation should be posted to the Forum.
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