Matrix

A matrix is a 2-dimensional array of numbers used for linear algebra operations. Matrices are created by calling the to_m() method on nested arrays.

Matrix supports mathematical operations:

• Matrix multiplication: m1 * m2
• Element-wise addition: m1 + m2
• Element-wise subtraction: m1 - m2

Matrix indexing:

• m[i] returns row i as an array
• m[i][j] returns the element at row i, column j
• Negative indices are supported: m[-1] returns the last row

m1 = [[1, 2], [3, 4]].to_m()
m2 = [[5, 6], [7, 8]].to_m()

result = m1 * m2
sum = m1 + m2
diff = m2 - m1

puts(result)

// should output
2x2 matrix
┌            ┐
│ 19.0  22.0 │
│ 43.0  50.0 │
└            ┘

Literal Specific Methods

col(INTEGER)

Returns ARRAY|ERROR

Returns the specified column as an array (0-indexed).

m = [[1, 2, 3], [4, 5, 6]].to_m()
m.col(1)

Output

[2.0, 5.0]

cols()

Returns INTEGER

Returns the number of columns in the matrix.

m = [[1, 2, 3], [4, 5, 6]].to_m()
m.cols()

Output

3

get(INTEGER, INTEGER)

Returns FLOAT|ERROR

Returns the element at the specified row and column (0-indexed).

m = [[1, 2, 3], [4, 5, 6]].to_m()
m.get(0, 2)

Output

3.0

row(INTEGER)

Returns ARRAY|ERROR

Returns the specified row as an array (0-indexed).

m = [[1, 2, 3], [4, 5, 6]].to_m()
m.row(0)

Output

[1.0, 2.0, 3.0]

rows()

Returns INTEGER

Returns the number of rows in the matrix.

m = [[1, 2, 3], [4, 5, 6]].to_m()
m.rows()

Output

2

set(INTEGER, INTEGER, FLOAT|INTEGER)

Returns NIL|ERROR

Sets the element at the specified row and column (0-indexed).

m = [[1, 2, 3], [4, 5, 6]].to_m()
m.set(0, 2, 99)
m

Output

2x3 matrix
┌               ┐
│ 1.0  2.0  3.0 │
│ 4.0  5.0  6.0 │
└               ┘
nil
2x3 matrix
┌                ┐
│ 1.0   2.0  99.0 │
│ 4.0   5.0   6.0 │
└                ┘

shape()

Returns ARRAY

Returns an array containing the dimensions [rows, cols] of the matrix.

m = [[1, 2, 3], [4, 5, 6]].to_m()
m.shape()

Output

[2, 3]

size()

Returns INTEGER

Returns the total number of elements in the matrix (rows * cols).

m = [[1, 2, 3], [4, 5, 6]].to_m()
m.size()

Output

6

t()

Returns MATRIX

Alias for transpose(). Returns the transposed matrix.

m = [[1, 2], [3, 4]].to_m()
m.t()

Output

2x2 matrix
┌          ┐
│ 1.0  3.0 │
│ 2.0  4.0 │
└          ┘

to_a()

Returns ARRAY

Converts the matrix back to a nested array representation.

m = [[1, 2], [3, 4]].to_m()
m.to_a()

Output

[[1.0, 2.0], [3.0, 4.0]]

transpose()

Returns MATRIX

Returns the transposed matrix (rows and columns swapped).

m = [[1, 2, 3], [4, 5, 6]].to_m()
m.transpose()

Output

3x2 matrix
┌          ┐
│ 1.0  4.0 │
│ 2.0  5.0 │
│ 3.0  6.0 │
└          ┘

Generic Literal Methods

methods()

Returns ARRAY

Returns an array of all supported methods names.

"test".methods()

Output

["upcase", "find", "format", "reverse", "split", "replace", "strip!", "count", "reverse!", "lines", "downcase!", "upcase!", "size", "strip", "downcase"]

to_f()

Returns FLOAT

If possible converts an object to its float representation. If not 0.0 is returned.

1.to_f()
"1.4".to_f()
nil.to_f()

Output

1.0
1.4
0.0

to_i()

Returns INTEGER

If possible converts an object to its integer representation. If not 0 is returned.

true.to_i()
false.to_i()
1234.to_i()
"4".to_i()
"10011010010"to_i(2)
"2322".to_i(8)
"0x2322".to_i()

Output

1
0
1234
4
1234
1234
1234

to_json()

Returns STRING|ERROR

Returns the object as json notation.

a = {"test": 1234}
a.to_json()

Output

{"test": 1234}
"{\"test\":1234}"

to_s()

Returns STRING

If possible converts an object to its string representation. If not empty string is returned.

true.to_s()
1234.to_s()
1234.to_s(2)
1234.to_s(8)
1234.to_s(10)
"test".to_s()
1.4.to_s()

Output

"true"
"1234"
"10011010010"
"2322"
"1234"
"test"
"1.4"

type()

Returns STRING

Returns the type of the object.

"test".type()

Output

"STRING"

wat()

Returns STRING

Returns the supported methods with usage information.

true.wat()

Output

"BOOLEAN supports the following methods:
to_s()"