GSL_Matrix class
Class methods
GSL_Matrix.new(argv)GSL_Matrix.alloc(argv)-
These methods create a GSL_Matrix object which contains matrix elements. One can initialize a matrix with arrays,
require 'gsl' m = GSL_Matrix::new([1, 2, 3], [6, 5, 4], [7, 8, 1]) -> a 3x3 matrix is created, 1 2 3 4 5 6 7 8 9With an array and rows&cols,
m = GSL_Matrix::new([1, 2, 3, 4, 5, 6, 7, 8, 9], 3, 3)
Methods
GSL_Matrix#set(argv)-
This method sets elements of the matrix in various manners.
with two integers and a number,
m.set(1, 2, 3.2) -> the (1, 2) element is set to 3.2
with arrays,
m.set([6, 5, 6], [4, 5, 7], [8, 5, 21]) -> 6 5 6 4 5 7 8 5 21with an array and sizes,
m.set([4, 5, 6, 8, 98, 6, 4, 3, 1], 3, 3) -> 4 5 6 8 98 6 4 3 1
GSL_Matrix#get(i, j)-
This method returns the (i,j)th element of the reciever matrix self.
GSL_Matrix#set_all(x)-
This method sets all the elements of the reciever matrix to the value x.
GSL_Matrix#set_zero-
This method sets all the elements of the matrix to zero.
GSL_Matrix#set_identity-
This method sets the elements of the reciever matrix to the corresponding elements of the identity matrix, i.e. a unit diagonal with all off-diagonal elements zero. This applies to both square and rectangular matrices.
GSL_Matrix#fprintf(io, format)-
This method writes the matrix elements line-by-line to the io object io using the format specifier format.
GSL_Matrix#fscanf(io)-
This method reads formatted data from the io object io into the matrix.
Creating row and column vectors
GSL_Matrix#row(i)-
This method returns a vector of the i-th row of the matrix.
GSL_Matrix#column(i)GSL_Matrix#col(i)-
These methods return a vector of the j-th column of the matrix.
GSL_Matrix#diagonal-
This method returns a vector of the diagonal of the matrix.
GSL_Matrix#set_row(i, v)-
This method copies the elements of the vector v into the i-th row of the matrix. The length of the vector must be the same as the length of the row.
GSL_Matrix#set_col(j, v)-
This method copies the elements of the vector v into the j-th column of the matrix. The length of the vector must be the same as the length of the column.
GSL_Matrix#swap_rows!(i, j)-
This method exchanges the i-th and j-th rows of the matrix in-place.
GSL_Matrix#swap_rows(i, j)-
Same as GSL_Matrix#swap_rows!(i, j), but not modifies the reciever, and returns a new matrix.
GSL_Matrix#swap_columns!(i, j)GSL_Matrix#swap_columns(i, j)-
This method exchanges the i-th and j-th columns of the matrix.
GSL_Matrix#swap_rowcol!(i, j)GSL_Matrix#swap_rowcol(i, j)-
This method exchanges the i-th row and j-th column of the matrix. The matrix must be square for this operation to be possible.
GSL_Matrix#transpose!-
This method returns a matrix of a transpose of the reciever matrix.
GSL_Matrix#transpose-
This method replaces the reciever matrix by its transpose by copying the elements of the matrix in-place. The matrix must be square for this operation to be possible.
Matrix operations
GSL_Matrix#add(b)GSL_Matrix#add!(b)-
This method adds the elements of matrix b to the elements of the reciever matrix. The two matrices must have the same dimensions.
GSL_Matrix#sub!(b)GSL_Matrix#sub(b)-
This method subtracts the elements of matrix b from the elements of the reciever matrix. The two matrices must have the same dimensions.
GSL_Matrix#mul_elements!(b)GSL_Matrix#mul_elements(b)-
This method multiplies the elements of the reciever matrix by the elements of matrix b. The two matrices must have the same dimensions.
GSL_Matrix#div_elements!(b)GSL_Matrix#div_elements(b)-
This method divides the elements of the reciever matrix by the elements of matrix b. The two matrices must have the same dimensions.
GSL_Matrix#scale!(x)GSL_Matrix#scale(x)-
This method multiplies the elements of the reciever matrix by the constant factor x.
GSL_Matrix#add_constant!(a)GSL_Matrix#add_constant(a)-
This method adds the constant value x to the elements of the matrix.
Finding maximum and minimum elements of matrices
GSL_Matrix#maxGSL_Matrix#min-
These methods return the max/min value in the reciever matrix.
GSL_Matrix#minmax-
This method returns a two elements array [min, max], which contains the minimum and the maximum values in the reciever matrix.
GSL_Matrix#max_indexGSL_Matrix#min_index-
These methods return the index of the max/min value in the reciever matrix.
GSL_Matrix#minmax_index-
This method returns a two elements array [imin, imax], which contains the indices of the minimum and the maximum value in the reciever matrix.
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GSL_Matrix#to_naGSL_Matrix#to_narrayGSL_Matrix#to_NArray-
This method converts a GSL_Matrix object into an NArray object, which is provided by the NArray extension developed by M.Tanaka. An NArray object is also converted into a GSL_Matrix object with the method to_m or to_gm.
ex) require 'narray' require 'gsl/gsl_array' # an NArray object m = NMatrix[[0, 1.2, 1],[1.5, 0, 2]] p m <----- NMatrix.float(3,2): [ [ 0.0, 1.2, 1.0 ], [ 1.5, 0.0, 2.0 ] ] # GSL_Matrix gm = m.to_gm p gm <---- [ 0.000e+00 1.200e+00 1.000e+00 1.500e+00 0.000e+00 2.000e+00 ] #<GSL::GSL_Matrix> # NArray m2 = gm.to_na p m2 <---- NArray.float(3,2): [ [ 0.0, 1.2, 1.0 ], [ 1.5, 0.0, 2.0 ] ]Note that you should compile Ruby/GSL with the option flag with-narray-include=... to use these methods.