I try `intval(6.02 * 100)`, the result is 602, but why the result of `intval(5.02 * 100)` is 501?

Question

I try intval(6.02 * 100),the result is 602。but why the result of intval(5.02 * 100) is 501?

Answer 1

This is a floating point math issue. The following might help explain it:

ini_set('precision', 17);
echo (float)5.02;

5.0199999999999996

echo 5.02 * 100;

501.99999999999994

echo intval(501.99999999999994);

501

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