These suggestions were made for SRFI 122; here are related items in the weird-domains branch of SRFI 231: https://github.com/gambiteer/srfi-231/tree/weird-domains On 1/11/20 6:57 PM, John Cowan wrote: > This is very preliminary, and was compiled by scouring features from > ISO/IEC 13751, Extended APL. > > (array-depth a) => examines all elements and recursively calls itself on > any elements that are arrays. Returns one more than its deepest array > element. Added as an example to the SRFI document. > > array-recursive-get and array-recursive-set: the same as calling the > array's getter and setter, but additional arguments are used to index an > element that is itself an array recursively until the arguments run > out. It is an error if there aren't enough arguments to index the array > or a particular nested array. A partial substitute is to call the getter of a curried array. > (recursive-array->list a) => similar to array->list, but any elements > that are arrays are recursively converted to lists. This result can > then be flattened to find all elements in all enclosed arrays. array->list*, array->vector*, with inverses list*->array, vector*->array > (iterated-list->specialized-array list . <make-specialized-array args>) > => similar to list->specialized-array but if the list is exhausted, > repeats its elements until the result array is full. No. > (array-fold-on proc knil a dim) => like array-fold, but instead of > processing all elements in lexicographic order, divides a into > sub-arrays on dimension dim and folds over the the sub-arrays instead. Added as an example to the SRFI document > (array-inner-product sum product a1 a2) => constructs the inner product > (dot product, matrix product) of a1 and a2, using the dyadic function > *product* to multiply individual elements and the variadic function > *sum* to total them. It is an error if the bounds of the last dimension > of a1 are not equal to the bounds of the first dimension of a2; the > bounds of the result are all the remaining bounds of a1 followed by all > the remaining bounds of a2. array-inner-product > (array-catenate a1 a2 dim) => glues together a1 and a2, which must have > the same interval, along dimension dim. We also need array-laminate, > but I have not worked that out yet. array-append, array-block, with inverse array-tile. There's also array-stack for array-laminate. > (array-find = a vec) => searches through the elements of a in > lexicographic order looking for the first element that is equal (in the > sense of the = argument) to an element of vec. The result is a vector > the same size as vec containing the indices of these occurrences, or #f > if there is no occurrence. No. > (array-grade < a dim) => slices a into subarrays along dimension dim and > returns a vector which specifies the permutation of the slices along > dimension dim that puts them in increasing order in the sense of the < > argument. No. > > (Of course any of these could be incorporated into SRFI 122bis.) > > A few more ideas not yet worked out: array-broadcast, array-expand, > array-replicate. > > Comments? > > > > John Cowan http://vrici.lojban.org/~cowan > <http://vrici.lojban.org/~cowan> xxxxxx@ccil.org <mailto:xxxxxx@ccil.org> > This great college [Trinity], of this ancient university [Cambridge], > has seen some strange sights. It has seen Wordsworth drunk and Porson > sober. And here am I, a better poet than Porson, and a better scholar > than Wordsworth, somewhere betwixt and between. --A.E. Housman >
