This help topic is for R version 2.9.0. For the current version of R, try https://stat.ethz.ch/R-manual/R-patched/library/base/html/sum.html
sum {base}R Documentation

Sum of Vector Elements

Description

sum returns the sum of all the values present in its arguments.

Usage

sum(..., na.rm = FALSE)

Arguments

...

numeric or complex or logical vectors.

na.rm

logical. Should missing values be removed?

Details

This is a generic function: methods can be defined for it directly or via the Summary group generic. For this to work properly, the arguments ... should be unnamed, and dispatch is on the first argument.

If na.rm is FALSE an NA value in any of the arguments will cause a value of NA to be returned, otherwise NA values are ignored.

Logical true values are regarded as one, false values as zero. For historical reasons, NULL is accepted and treated as if it were integer(0).

Value

The sum. If all of ... are of type integer or logical, then the sum is integer, and in that case the result will be NA (with a warning) if integer overflow occurs. Otherwise it is a length-one numeric or complex vector.

NB: the sum of an empty set is zero, by definition.

S4 methods

This is part of the S4 Summary group generic. Methods for it must use the signature x, ..., na.rm.

‘plotmath’ for the use of sum in plot annotation.

References

Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988) The New S Language. Wadsworth & Brooks/Cole.

See Also

colSums for row and column sums.


[Package base version 2.9.0 ]