split_vector: Split a vector into smaller pieces
In LAJordanger/leanRcoding: Leaner R Coding

This function chops a vector into a given number of pieces, and it tries to do this by making them as similar in length as possible. This function is used when splitting an array into chunks in order for foreach to work upon them in parallel, and it is also used in splitting that aims to avoid out-of-memory errors (due to large intermediate objects) by creating sizeable chunks that stays below a memory-limit. It does also allow additional stuff to be stored in the result, see details below.

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split_vector(vec, pieces, allow_extra_pieces = FALSE,
  compute_name = NULL, subset_name = NULL, add_to_compute = NULL,
  position = 1)

`vec`	The vector we want to split.
`pieces`	The number of chunks we want in the end.
`allow_extra_pieces`	Logical argument, default value `FALSE`. Use `TRUE` when this function is used as a tool for splitting up computations in order to get them below a critical threshold in relation to memory, in which case it's safer to allow pieces to take care of the remainder than to hope that it still should work. ## TASK: Explain this better later on.
`compute_name`	Use this to specify the name to be used in the compute-part of the resulting list. When the default `NULL` is used, a name will be created based on `vec`.
`subset_name`	Use this to specify the name to be used in the subset-part of the resulting list. When the default `NULL` is used, a name will be created based on `vec`.
`add_to_compute`	`list`, default `NULL`. Some functions might want more stuff in the compute-list, and this argument can then be used to add that stuff.
`position`	An integer, default value 1, that only should be used when `add_to_compute` is used. Use this argument to ensure that the splitting of the vector occurs at the desired `position` within the resulting `compute`-list, which might be desirable if e.g. `array` should be used to create a restricted array based on the splitting of a dimension `vec`.

This function returns a list with three components: pieces, a vector that we want to loop over, and, subset and compute that respectively gives the arguments needed by the function 'restrict' (that also can do replacements) and the function that performs the computation of interest.

LAJordanger/leanRcoding documentation built on Feb. 27, 2020, 4:42 p.m.