In deandevl/RmatrixPkg: Providing R functions for manipulating matrices

options(knitr.table.format = "html", width = 140)
knitr::opts_chunk$set(echo = TRUE, message = FALSE, warning = FALSE, fig.width = 8, fig.height = 8)

Author: Rick Dean

Article date: `r params$date`

library(knitr)
library(RmatrixPkg)

Define two vectors

v_vec <- c(4, 2)
x_vec <- c(7, 6)

to_vectors <- rbind(v_vec, x_vec)
to_labels <- c("v_vec(4,2)", "x_vec(7,6)")
RmatrixPkg::plot_vector_2d(
  to = to_vectors, 
  vector_labels = to_labels,
  x_breaks = c(-1,10,1),
  y_breaks = c(-1,10,1)
)

Project x_vec onto v_vec

v_vec <- c(4, 2)
x_vec <- c(7, 6)

proj_x <- RmatrixPkg::proj_vector(x = x_vec, v = v_vec)
proj_str <- RmatrixPkg::matrix_to_latex(x = proj_x)

The projection is located at r proj_str

v_vec <- c(0, 0, 4, 2)
x_vec <- c(0, 0, 7, 6)
p_vec <- c(0, 0, proj_x[1], proj_x[2])
c_vec <- c(7, 6, proj_x[1], proj_x[2])

from_to <- rbind(v_vec, x_vec, p_vec, c_vec)
from_to_labels <- c("v_vec(4,2)", "x_vec(7,6)", "p_vec(8,4)", "")
vector_colors <- c("red", "black", "black", "blue")
RmatrixPkg::plot_vector_2d(
  from_to = from_to, 
  vector_labels = from_to_labels,
  vector_colors = vector_colors,
  x_breaks = c(-1,10,1),
  y_breaks = c(-1,10,1)
)