a stands for the entire array, which is the same as omitting the subscripts entirely and using a alone.įor any array, say Z, the dimension vector may be referenced explicitly as dim(Z) (on either side of an assignment).Īlso, if an array name is given with just one subscript or index vector, then the corresponding values of the data vector only are used in this case the dimension vector is ignored. More generally, subsections of an array may be specified by giving a sequence of index vectors in place of subscripts however if any index position is given an empty index vector, then the full range of that subscript is taken.Ĭontinuing the previous example, a is a 4 * 2 array with dimension vector c(4,2) and data vector containing the valuesĬ(a, a, a, a, Individual elements of an array may be referenced by giving the name of the array followed by the subscripts in square brackets, separated by commas. ![]() The values in the data vector give the values in the array in the same order as they would occur in FORTRAN, that is “column major order,” with the first subscript moving fastest and the last subscript slowest.įor example if the dimension vector for an array, say a, is c(3,4,2) then there are 3 * 4 * 2 = 24 entries in a and the data vector holds them in the order a, a, …, a, a.Īrrays can be one-dimensional: such arrays are usually treated in the same way as vectors (including when printing), but the exceptions can cause confusion.ĥ.2 Array indexing. Other functions such as matrix() and array() are available for simpler and more natural looking assignments, as we shall see in The array() function. ![]() ![]() Gives it the dim attribute that allows it to be treated as a 3 by 5 by 100 array.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |