Unexpected division result in Swift -

Unexpected division result in Swift -

i trying create metronome application in swift, , i'm having awkward results. here code :

@ibaction func playstop(sender: anyobject) { if !timer.valid{ println(double(60/tempo)) timer = nstimer(timeinterval: nstimeinterval(double(60/(tempo))), target: self, selector: "update", userinfo: nil, repeats: true) nsrunloop.currentrunloop().addtimer(timer, formode: nsdefaultrunloopmode) } else{ timer.invalidate() } } func control(_control: nscontrol, textshouldendediting fieldeditor: nstext) -> bool { if (tempolabel.integervalue <= 0) { homecoming false } tempo = tempolabel.integervalue timer.invalidate() println(tempo) playstop(self) homecoming true }

the tempo set user nstextfield number formatter, , set 60 default. when value of text field changed, console explicitly writes right value tempo variable, , programme works fine if tempo set 60. when value isn't 60, result double(60/tempo) equals 0, every time, , update function gets called if in infinite loop. using double(60/tempo), float(60/tempo) or 60/tempo doesn't alter anything. don't understand why such result, or how can solve it.

cast numerator or denominator double.

do 60.0/tempo or 60/double (tempo)

swift division