| GramSchmidt {rgl} | R Documentation |
The Gram-Schmidt algorithm
Description
Generate a 3x3 orthogonal matrix using the Gram-Schmidt algorithm.
Usage
GramSchmidt(v1, v2, v3, order = 1:3)
Arguments
v1, v2, v3 |
Three length 3 vectors (taken as row vectors). |
order |
The precedence order for the vectors; see Details. |
Details
This function orthogonalizes the matrix rbind(v1, v2, v3)
using the Gram-Schmidt algorithm. It can handle rank 2 matrices
(returning a rank 3 matrix). If the original is rank 1, it is likely
to fail.
The order vector determines the precedence of the original
vectors. For example, if it is c(i, j, k), then row i
will be unchanged (other than normalization); row j will
normally be transformed within the span of rows i and j.
Row k will be transformed orthogonally to the span of
the others.
Value
A 3x3 matrix whose rows are the orthogonalization of the original row vectors.
Author(s)
Duncan Murdoch
Examples
# Proceed through the rows in order
print(A <- matrix(rnorm(9), 3, 3))
GramSchmidt(A[1, ], A[2, ], A[3, ])
# Keep the middle row unchanged
print(A <- matrix(c(rnorm(2), 0, 1, 0, 0, rnorm(3)), 3, 3, byrow = TRUE))
GramSchmidt(A[1, ], A[2, ], A[3, ], order = c(2, 1, 3))