Histograms with polymorphic bin types.

A histogram is a list of bins, each with a count. Bin `i`

is
defined by a lower limit `lo(i)`

and an upper limit `hi(i)`

. It is
inclusive of the lower limit and exclusive of the upper limit. For
all `i`

, `hi(i) = lo(i+1)`

. By convention the first bin is
numbered 0. The count of a bin is a floating point number,
allowing fractional values if necessary.

`module Biocaml_histogram: `

`sig`

`type ``'a`

t

The type of a histogram whose bin limits are of type

`'a`

.`val make : ``('a -> 'a -> int) -> 'a list -> 'a t option`

`make cmp bins`

returns a new histogram from the given `bins`

,
all initialized to a count of 0.0. The `bins`

must be provided as a
list of the boundaries dividing them. The list `[v0; v1; ...; vn]`

of length `n+1`

represents the `n`

bins `[v0, v1)`

, `[v1, v2)`

,
..., `[vn-1, vn)`

, where `cmp`

is used as the comparison
function. Resturns `None`

if `bins`

are not monotonically
increasing, or if length of `bins`

is less than 2.`val to_list : ``'a t -> (('a * 'a) * float) list`

Return a list of all bin/count pairs. Answer will be in
ascending order by the bin limits.

`val bin_exn : ``'a t -> int -> 'a * 'a`

`bin hist i`

returns the `i`

th bin of `hist`

. Raise
`Invalid_argument`

if an invalid bin number is requested.`val count_exn : ``'a t -> int -> float`

`count hist i`

returns the count the `i`

th bin. Raise
`Invalid_argument`

if an invalid bin number is requested.`val increment : ``?delt:float -> 'a t -> 'a -> 'a t`

`increment delt hist x`

increments the count of the bin containing
`x`

by `delt`

(default is 1.0). The histogram is unaltered if `x`

not
in any bin. This is not considered an error because it is often
necessary to calculate a histogram for a subset of a larger data
set.`val find_bin_index : ``'a t -> 'a -> int option`

`find_bin_index hist x`

returns the index of the bin in `hist`

containing `x`

. Return None if `x`

is outside the histogram's
range.`val in_range : ``'a t -> 'a -> bool`

`in_range hist x`

is true if `x`

greater than or equal to ```
minimum
hist
```

and strictly less than `maximum hist`

.`val make_uniform : ``float ->`

float -> int -> (float t, string) Core.Std.Result.t

`make_uniform min max n`

returns a histogram with `n`

bins
uniformly dividing up the range from `min`

to `max`

. Bins will be
inclusive of the lower limit and exclusive of the upper limit,
i.e. value of `min`

will fall into lowest bin and value of `max`

will
fall outside the range of the histogram. Raise `Failure`

if `min`

not
strictly less than `max`

or if `n`

not greater than 0.`end`