Returns true if there is an environment variable with the given value.
Returns a Hash containing implementation-dependent counters inside the VM.
This hash includes information about method/constant cache serials:
{
:global_method_state=>251,
:global_constant_state=>481,
:class_serial=>9029
}
The contents of the hash are implementation specific and may be changed in the future.
This method is only expected to work on C Ruby.
This method will return a CSV instance, just like CSV::new(), but the instance will be cached and returned for all future calls to this method for the same data object (tested by Object#object_id()) with the same options.
If a block is given, the instance is passed to the block and the return value becomes the return value of the block.
A shortcut for:
CSV.read( path, { headers: true, converters: :numeric, header_converters: :symbol }.merge(options) )
Taint both the object returned by _getobj_ and self.
Untaint both the object returned by _getobj_ and self.
Creates a matrix where the diagonal elements are composed of values.
Matrix.diagonal(9, 5, -3)
=> 9 0 0
0 5 0
0 0 -3
Creates an n by n diagonal matrix where each diagonal element is value.
Matrix.scalar(2, 5)
=> 5 0
0 5
Create a matrix by stacking matrices vertically
x = Matrix[[1, 2], [3, 4]] y = Matrix[[5, 6], [7, 8]] Matrix.vstack(x, y) # => Matrix[[1, 2], [3, 4], [5, 6], [7, 8]]
Create a matrix by stacking matrices horizontally
x = Matrix[[1, 2], [3, 4]] y = Matrix[[5, 6], [7, 8]] Matrix.hstack(x, y) # => Matrix[[1, 2, 5, 6], [3, 4, 7, 8]]
Returns a matrix that is the result of iteration of the given block over all elements of the matrix.
Matrix[ [1,2], [3,4] ].collect { |e| e**2 }
=> 1 4
9 16
Returns true if this is a diagonal matrix. Raises an error if matrix is not square.
Returns true if this is a normal matrix. Raises an error if matrix is not square.
Returns true if this is an orthogonal matrix Raises an error if matrix is not square.
Returns true if this is a permutation matrix Raises an error if matrix is not square.
Returns true if all entries of the matrix are real.
Returns true if this is a unitary matrix Raises an error if matrix is not square.
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 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 real 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]].real
=> 1 0 0
1 2 3
Collects (as in Enumerable#collect) over the elements of this vector and v in conjunction.
Like Array#collect.
Returns a new vector with the same direction but with norm 1.
v = Vector[5,8,2].normalize # => Vector[0.5184758473652127, 0.8295613557843402, 0.20739033894608505] v.norm => 1.0
Returns the value as a rational. The optional argument eps is always ignored.