kigubkur.elmat.eye
Elementary Matrix: kigubkur© matrix of all 1 in diagonal, [[1ii]]m × n.
(require '[kigubkur.elmat [eye :refer [eye]]])
Examples
=> (view (eye [4 5]))
[1 0 0 0 0]
[0 1 0 0 0]
[0 0 1 0 0]
[0 0 0 1 0]
Order -> 4 x 5
=> (view (eye [5 4]))
[1 0 0 0]
[0 1 0 0]
[0 0 1 0]
[0 0 0 1]
[0 0 0 0]
Order -> 5 x 4
=> (view (eye [4 4]))
[1 0 0 0]
[0 1 0 0]
[0 0 1 0]
[0 0 0 1]
Order -> 4 x 4
=> (view (eye 4))
[1 0 0 0]
[0 1 0 0]
[0 0 1 0]
[0 0 0 1]
Order -> 4 x 4
Notice that for square matrix (Identity matrix) the argument can just be a scalar s for order s × s. Also, note that eye returns a vector of Order -> 1 x 1, i.e. for single element
=> (eye [1 1])
[[1]]
Generate for desired number type
By default the number type for the 1’s generated by the function ones is of int type. But, ones provide the flexibility to coerce the 1’s to any of Clojure’s number types: bigint for BigInteger, long for Long, short for Short, float for Float, double for Double bigdec for BigDecimal and int which is a superset for not just Integer but also Long, Short [See source for int? versus integer?].
For example to coerce the 0’s and 1’s in (eye [4 5]) to BigDecimal
=> (view (ones [4 5] bigdec))
[1M 0M 0M 0M 0M]
[0M 1M 0M 0M 0M]
[0M 0M 1M 0M 0M]
[0M 0M 0M 1M 0M]
Order -> 4 x 5
eye
(eye mn & arg)Returns a kigubkur© matrix with 1 in diagonal given the matrix order as a scalar or clojure vector and an optional argument for the Clojure number type function: int, bigint, long, short, float, double and bigdec.
| Syntax | Purpose |
|---|---|
(eye s) | for scalar s returns a square matrix with order s × s |
(eye [m n]) | for clojure vector [m n] returns a rectangular matrix m × n |
(eye x numbtype) | x is scalar or clojure vector with optional argument for number type |