Converting "minutes.seconds.milliseconds" to "seconds.milliseconds"

Question

Hello
I have string (string a = 1.15.67) which represents time (minutes. seconds. milliseconds).
Which is the easiest way to get a Double which holds the above mentioned time, where minutes are converted to seconds (double b = 75.67)?
Should i convert the above mentioned String to a Date object first or is this not neccesary?
Edited by: user10496629 on 17.03.2011 14:03

Answer 1

jduprez wrote:
To be honest, my knowledge of FP arithmetic comes mostly from reading this forum, and I'm sure you contributed to such discussions in the past - so I'm surprised to read your arguments.
Except myself I would use integral types (int, or long to be conservative) to hold the number of seconds/milliseconds. I don't see what double would bring except inaccurracy that will build up when you add/combine multiple durations.Yeah, but given that he wants the end result to include a fractional piece, he's going to have inaccuracies anyway?
Not if he stores the number of milliseconds, and only formats it at display time.Oh, I see what you're saying now.
Still, unless he's dealing with very large scales, he can store as a double, format for display, and any inaccuracies will wash out in the format. That is, even though 12345.67 cannot be stored in a double, most likely he will be able to ignore that, store 12345.67000000001, and format it so that it displays as 12345.67.
Whether that or a separate integer piece representation is more appropriate depends on other requirements and use cases that the OP hasn't shared with us. :-)
>
And it's highly likely that the integer numbers of minutes, seconds, and millis that are represented individually will be exactly representable by double.
In fact, if he keeps millis and seconds in their expected ranges, it's guaranteed that they are, and the only possible parsing inaccuracy is in minutes, and even then, the entire range of int can be exactly represented, so it'd be an awful lot of minutes before he started losing precision there.Either I misunderstand you, or what you say is not correct:
System.out.println(0.1D+0.2D+0.3D);Results in:
0.6000000000000001
But when you format for display, you'll get 0.600.