From: Paul A Bristow (pbristow_at_[hidden])
Date: 2006-07-11 12:33:26
| -----Original Message-----
| From: boost-bounces_at_[hidden]
| [mailto:boost-bounces_at_[hidden]] On Behalf Of Deane Yang
| Sent: 11 July 2006 17:15
| To: boost_at_[hidden]
| Subject: Re: [boost] [math/staticstics/design] How best
| > What about the Qs? (complements)
| In other words, 1 - P. Right? One response is why do you
| need to define
| it, given how easy it is to get from the cumulative density function?
| If not, use a common name for it. Unfortunately, I don't have a good
Perhaps not really needed? Is there an accuracy reason for both?
| I've always seen it referred to as the cumulative density function (CDF
Agree common - but not all.
| > But excessively long :-(
| Compared to what? I personally am very grateful that I no longer see
| short, cryptic function and variable names in code.
OK, I'm persuaded, but what to others think?
| Here's a first stab (I'm sure it can be improved):
| class StudentsT
| explicit StudentsT(double degrees_of_freedom);
| double density(double x) const;
| double cumulative_probability(double x) const;
| double quantile(double probability) const;
| // Also known as inverse cumulative.
| double degrees_of_freedom(double quantile, double probability)
| // Functions below may return NaN, if undefined.
| double mean() const;
| double variance() const;
| double skewness() const;
| double kurtosis() const;
Thanks - I think I like it.
PS Never written a line of C in my life ;-)
--- Paul A Bristow Prizet Farmhouse, Kendal, Cumbria UK LA8 8AB +44 1539561830 & SMS, Mobile +44 7714 330204 & SMS pbristow_at_[hidden]
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