frame/filter

src/frame/filter.tur

defn

filter-mask

(filter-mask [f :int mask :int] :int)

return a new frame containing rows where mask = 1.

defn

(distinct [f :int names :int] :int)

return a new frame with duplicate rows removed.

Parameters

f		:int frame
names		cons list of :cstr column names that define the key. If 0
		(nil), all columns are used.

Returns

:int new frame containing one row per unique key tuple, in the order the first occurrence appeared after sorting by the key columns.

Since: FR7

defn

(sample [f :int n :int seed :int] :int)

return a new frame with `n` rows chosen uniformly at random

Since: FR7

Internal definitions

__f-nil

__f-cons

__filter-clone-field-at

__column-take-mask-- build a new column containing rows of `col` whose

__count-set-bits-- count 1-bits in the first n bits of mask. Since: FR2

__take-cols

__clone-fields

__filter-take-- build a new frame from f by selecting rows in `indices`

__list-to-int-array

__free-int-array

__take-all-cols

__f-so-take

__distinct-first-rows-- given a frame, key-name list, and the

__g-first-row-- accessor for grouped-frame's perm[group_starts[gi]].

__cstr-as-int

__all-column-names

__sample-indices-- produce an int64_t* of `n` distinct random indices in