%**% {onlineforecast} | R Documentation |
Multiplication of list with y, elementwise
Description
Multiplication of each element in a list (x) with y
Usage
x %**% y
Arguments
x |
a list of matrices, data.frames, etc. |
y |
a vector, data.frame or matrix |
Details
Each element of x is multiplied with y using the usual elementwise '*' operator.
Typical use is when a function, e.g. bspline()
, returns a list of matrices (e.g. one for each base spline) and they should individually be multiplied with y (a vector, matrix, etc.).
Since this is intended to be used for forecast models in the transformation stage then there are some percularities:
If the number of columns or the names of the columns are not equal for one element in x and y, then only the columns with same names are used, hence the resulting matrices can be of lower dimensions.
See the example https://onlineforecasting.org/examples/solar-power-forecasting.html where the operator is used.
Value
A list of same length of x
Examples
x <- list(matrix(1:9,3), matrix(9:1,3))
x
y <- matrix(2,3,3)
y
x %**% y
y <- 1:3
x %**% y
# Naming percularity
nams(x[[1]]) <- c("k1","k2","k3")
nams(x[[2]]) <- c("k2","k3","k4")
y <- matrix(2,3,3)
nams(y) <- c("k1","k3","k7")
# Now the only the horizons matching will be used
x %**% y