Efficiency: whole vector and for loop methods
On Wed, 2 Apr 2003, graham lawrence wrote:
Dear R-help, As a generalization, is it more efficient to use a single method to selectively transform items in a matrix? Preferably whole-vector, yes; but if one of the column vectors compels the use of a "for loop", is it then faster to do all of the transformations for the matrix via that "for loop", rather than use a mixture of methods on a column-wise basis?
Hard to say. My guess is that a mixture of methods would be faster, but the only reliable answer to 'is it faster' is to try it and see. -thomas