Vectors and Matrices

VecNf is a dense vector of Float (IEEE-754 float64) of length N, chosen when you call .new^. Mat2f is a dense rank-2 matrix of the same cell type, with shape rows × cols fixed at construction. Both start zero-filled.

They are not Lists: there is no append. Index stores require a valid slot and a Float — Final does not coerce Int into these cells.

Filling from a stack of values uses the [ … ] filler (the closer does not create the instance). See Collection Builders for nesting rules.

VecNf

Kind	Name	Effect	Description
class	`new`	`( n:i -- v:VecNf )`	zero-filled vector; `n` must be > 0
prop	`len`	`( -- len:i )`	number of cells

Indexed access is the List-style ordinal pair:

cs:@()   // ( index:i -- f:Float )
cs:!()   // ( val:Float index:i -- )

3 VecNf.new^ >ts
[ 1. 2. 3. ]
0 t:@() $ nl          // 1
9. 1 t:!()            // replace index 1
t:drop

foreach walks cells in order 0 … len-1. The loop value i is each Float.

Mat2f

Kind	Name	Effect	Description
class	`new`	`( rows:i cols:i -- m:Mat2f )`	zero-filled; both dimensions > 0
prop	`rows`	`( -- rows:i )`	row count
prop	`cols`	`( -- cols:i )`	column count
prop	`len`	`( -- len:i )`	`rows * cols`
method	`getRowIter`	`( -- rows:Range )`	row indexes `0 … rows−1`
method	`getColIter`	`( -- cols:Range )`	column indexes `0 … cols−1`
method	`wrap`	`( row:i col:i -- row:i col:i )`	torus wrap of coordinates

Two index styles:

Affix	Stack	Meaning
`@()` / `!()`	`( index:i -- f )` / `( f index:i -- )`	flat row-major index `0 … len-1`
`@[]` / `![]`	`( r:i c:i -- f )` / `( f r:i c:i -- )`	coordinates `(row, col)`

Teaching line: @() = flat; @[] = coordinates.

2 3 Mat2f.new^ >ts
[
  0. 1. 2.
  3. 4. 5.
]
1 2 t:@[] $ nl        // 5  (row 1, col 2)
9. 0 0 t:![]          // put 9 at (0,0)
t:drop

foreach on a Mat2f walks flat cells in row-major order; i is each Float. Nested range loops plus @[] walk by coordinates (i is the inner index, j the outer):

: showMat
  2 2 Mat2f.new^ [ 1. 2.  3. 4. ] >ts
  0 t:.rows@ 1 - range
  foreach
    0 t:.cols@ 1 - range
    foreach
      j i t:@[] $ sp
    /foreach
    nl
  /foreach
  t:drop
;

.getRowIter^ / .getColIter^ return a Range over indexes if you do not want to write 0 .rows@ 1- range by hand. Pull a whole row or column as a new VecNf with mat::row / mat::col — operators.

Notes

Every [ … ] fill must supply exactly .len values, each already a Float.
Prefer VecNf / Mat2f when every cell is a Float and the shape is known (design matrix X, outcome y, coefficients). Prefer numeric Lists when the sequence still needs to grow.
help VecNf / help Mat2f lists members and accessors.

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Final — Introduction

Vectors and Matrices

VecNf

Mat2f

Notes