How to count Occurrences in a cross table in R?

How can I create a cross table in R (RStudio), where I count occurrences.

I have this sample input:

Technology <- c("A", "A", "B", "C", "C", "C")
Development <- c(1, 0, 1, 1, 1, 1)
Production <- c(1, 1, 0, 0, 0, 1)
Sales <- c(0, 0, 1, 1, 0, 1)
DF <- data.frame(Technology, Development, Production, Sales)

I want to know in which domain which technology is used most often.

The result should look like in the picture.

These problems are many times a data format problem and the solution is to reshape from wide to long format first, see this question.

Here is a base R solution with reshape and cross tabulation with xtabs.

Technology <- c("A", "A", "B", "C", "C", "C")
Development <- c(1, 0, 1, 1, 1, 1)
Production <- c(1, 1, 0, 0, 0, 1)
Sales <- c(0, 0, 1, 1, 0, 1)
DF <- data.frame(Technology, Development, Production, Sales)

reshape(
  DF,
  direction = "long",
  varying = list(names(DF[-1])),
  v.names = "Active",
  times = names(DF[-1]),
  timevar = "Phase"
) |>
  (\(x) xtabs(Active ~ Phase + Technology, x))()
#>              Technology
#> Phase         A B C
#>   Development 1 1 3
#>   Production  2 0 1
#>   Sales       0 1 2

^{Created on 2022-04-18 by the reprex package (v2.0.1)}

And a tidyverse solution.

suppressPackageStartupMessages({
  library(magrittr)
  library(tidyr)
})

DF %>%
  pivot_longer(-Technology) %>%
  xtabs(value ~ name + Technology, .)
#>              Technology
#> name          A B C
#>   Development 1 1 3
#>   Production  2 0 1
#>   Sales       0 1 2

^{Created on 2022-04-18 by the reprex package (v2.0.1)}