Solve Linear Equations and Invert Matrices - Generic Function
DESCRIPTION:
Performs matrix inversion if given a single argument, or solves systems
of linear equations if given two arguments.
This function is an S Version 3 generic (see Methods);
method functions can be written to handle specific
S Version 3 classes of data. Classes which already
have methods for this function include:
svd.right
,
upper.
USAGE:
solve(a, b, ...)
solve.default(a, b)
REQUIRED ARGUMENTS:
a
a representation of a square non-singular matrix.
In particular a QR decomposition as output by the
qr function is suitable.
OPTIONAL ARGUMENTS:
b
vector or matrix of coefficients.
VALUE:
the solution
x to the system of equations a %*% x = b, if
b is
present. Otherwise, the inverse of
a.
DETAILS:
If given a non-singular matrix
a, will give the inversion of the matrix.
If given two arguments,
a and
b, will give the solution
x for the
system of equations.
SEE ALSO:
,
,
,
,
.
for the transpose of a matrix.
for a generalized matrix inverse (matrix may be singular).
to solve a system of nonlinear equations (using function
solveNonlinear
in Examples section).
EXAMPLES:
amat <- matrix(c(19,8,11,2,18,17,15,19,10), nrow = 3)
ainv <- solve(amat) # invert amat
aqr <- qr(amat)
b1 <- c(9,5,14)
solve(aqr, b1)