tropicalSparse (version 0.1.0)

tropicalsparse.mv: tropicalsparse.mv()

Description

tropicalsparse.mv function performs the matrix-vector operation on the equation: y = alpha * op(A) * x + beta * y.

Usage

tropicalsparse.mv(alpha = NULL, A, opA = FALSE, x, beta = NULL, y,
  store = NULL, algebraType)

Arguments

alpha

is a single real value.

A

is a matrix.

opA

is transpose of A.

x

is a vector.

beta

is a single real value.

y

is a vector.

store

is storage technique.

algebraType

is string input that can be minplus or maxplus.

Value

Returns the resultant matrix.

Details

The input of this function is one matrix, transpose of that matrix, two vectors, two constants, storage technique and type of Tropical Algebra. The inputs of the matrix, vectors and algebraType are compulsory while all other inputs are optional. The matrix must be sparse otherwise error occured. alpha and beta must be a single real value. opA can be set to TRUE to take transpose of A. store input can be coo, csc and csr for applying following storage techniques respectively: Coordinate-Wise, Compressed Sparse Row, Compressed Sparse Column. If store is not specified then functionality is performed without using any storage technique. algebraType is used to specify type of Tropical Algebra. This can be minplus or maxplus. For more details about algebraType, see detail section of check.infinityM or check.infinityV. First of all A is multiplied with x and if alpha is given then the product of A and x will be multipied with alpha otherwise it remais the same. After this, beta is multiplied with y only if beta is given. Finally, both result are added to each other and the resultant matrix is obtained. Same functionailty is applied if any of the store technique is specified.

Examples

# NOT RUN {
a <- matrix(data = c(2, Inf, Inf, 0, Inf, Inf, Inf, 10, Inf),
nrow = 3, ncol = 3, byrow = TRUE)

b <- c(2, Inf, 5)

c <- c(Inf, 9, Inf)

tropicalsparse.mv(A = a, alpha = 5, opA = TRUE, x = b, y = c,
store = 'csr', algebraType = 'minplus')

#      [,1] [,2] [,3]
# [1,]    9  Inf  Inf
# [2,]    9    9    9
# [3,]  Inf   20  Inf

# }