Returns a section of the matrix. The parameters are either:
start_row, nrows, start_col, ncols; OR
row_range, col_range
Matrix.diagonal(9, 5, -3).minor(0..1, 0..2) => 9 0 0 0 5 0
Like Array#[]
, negative indices count backward from the end of the row or column (-1 is the last element). Returns nil if the starting row or column is greater than row_count
or column_count
respectively.
Returns the determinant of the matrix.
Beware that using Float
values can yield erroneous results because of their lack of precision. Consider using exact types like Rational
or BigDecimal
instead.
Matrix[[7,6], [3,9]].determinant => 45
deprecated; use Matrix#determinant
Returns a new matrix resulting by stacking horizontally the receiver with the given matrices
x = Matrix[[1, 2], [3, 4]] y = Matrix[[5, 6], [7, 8]] x.hstack(y) # => Matrix[[1, 2, 5, 6], [3, 4, 7, 8]]
Returns the trace (sum of diagonal elements) of the matrix.
Matrix[[7,6], [3,9]].trace => 16
Returns the transpose of the matrix.
Matrix[[1,2], [3,4], [5,6]] => 1 2 3 4 5 6 Matrix[[1,2], [3,4], [5,6]].transpose => 1 3 5 2 4 6
Returns a new matrix resulting by stacking vertically the receiver with the given matrices
x = Matrix[[1, 2], [3, 4]] y = Matrix[[5, 6], [7, 8]] x.vstack(y) # => Matrix[[1, 2], [3, 4], [5, 6], [7, 8]]
Returns the Eigensystem of the matrix; see EigenvalueDecomposition
.
m = Matrix[[1, 2], [3, 4]] v, d, v_inv = m.eigensystem d.diagonal? # => true v.inv == v_inv # => true (v * d * v_inv).round(5) == m # => true
Returns the imaginary part of the matrix.
Matrix[[Complex(1,2), Complex(0,1), 0], [1, 2, 3]] => 1+2i i 0 1 2 3 Matrix[[Complex(1,2), Complex(0,1), 0], [1, 2, 3]].imaginary => 2i i 0 0 0 0
Overrides Object#inspect
Returns true
iff all of vectors are linearly independent.
Vector.independent?(Vector[1,0], Vector[0,1]) => true Vector.independent?(Vector[1,2], Vector[2,4]) => false
Returns true
iff all of vectors are linearly independent.
Vector[1,0].independent?(Vector[0,1]) => true Vector[1,2].independent?(Vector[2,4]) => false
Overrides Object#inspect
Returns an incremented value of default
according to arg
.
Terminates option parsing. Optional parameter arg
is a string pushed back to be the first non-option argument.
Puts option summary into to
and returns to
. Yields each line if a block is given.
to
Output destination, which must have method <<. Defaults to [].
width
Width of left side, defaults to @summary_width.
max
Maximum length allowed for left side, defaults to width
- 1.
indent
Indentation, defaults to @summary_indent.
Returns the number of elements in the match array.
m = /(.)(.)(\d+)(\d)/.match("THX1138.") m.length #=> 5 m.size #=> 5
Returns the offset of the start of the nth element of the match array in the string. n can be a string or symbol to reference a named capture.
m = /(.)(.)(\d+)(\d)/.match("THX1138.") m.begin(0) #=> 1 m.begin(2) #=> 2 m = /(?<foo>.)(.)(?<bar>.)/.match("hoge") p m.begin(:foo) #=> 0 p m.begin(:bar) #=> 2