I have a problem with Math.sin
. I thought it would output the sinus of the given integer. So I tried Math.sin(30)
and my output was -0.9880316240928618
and then I checked with my calculator and it was 0.5.
I have a problem with Math.sin
. I thought it would output the sinus of the given integer. So I tried Math.sin(30)
and my output was -0.9880316240928618
and then I checked with my calculator and it was 0.5.
Parameters are assumed to be in radians, not degrees.
Try
Math.sin(Math.PI * (30/180));
A comment below notes that pre-computing the ratio π/180 is a good idea. One could add a companion to Math.sin
that works on degrees this way:
Math.dsin = function() {
var piRatio = Math.PI / 180;
return function dsin(degrees) {
return Math.sin(degrees * piRatio);
};
}();
(Some people don't like extending built-in objects, but since one doesn't instantiate Math instances — at least, I don't — this doesn't seem terribly offensive.)