row_sums {strider} | R Documentation |
Demonstration of fast row and columns sums in C++
row_sums(x)
col_sums(x)
x |
a numeric matrix |
A very efficient row summing algorithm that demonstrates
the use of the strided pointer concept. The row_sum
algorithm is
roughly twice as fast as rowSums
. The col_sum
algorithm
matches colSums
for speed.
row_sums(matrix(1:9, 3))
col_sums(matrix(1:9, 3))