Re: tempo as REAL number

[karl]

dak:
> jan <address@hidden> writes:
...
> >     \tempo 4 = 82.3
> > produces the error.
> > "syntax error, unexpected REAL"
> > Since in midi tempo definitions are of type float
> 
> They aren't.  They are exact fractions.
> 
> > I wonder if there is a reason for Lilypond to restrict the tempo to
> > integers. If there is no reason, I would like to suggest to make the
> > tempo command more general and accept reals.
> 
> Inexact numbers would make LilyPond's Midi output unpredictable
> (unsuitable for binary comparison).  I am not sure this would be a
> problem: we have the same situation with the extensive floating point
> calculations involved in the printed output.

midi's view of tempo is microseconds per midi quarter note, or 
(though I find midi's time and time sig. handling confusing)

 midi_tempo = 60*1000*1000 / "\tempo 4 value"

and

 60000000 / 82.3 about= 729040.09720534629404617253

I doubt that truncating/rounding that to a int vould cause any problem.

Regards,
/Karl Hammar

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