R: Compute Check Sum

cksum {bitops} | R Documentation

## Compute Check Sum

### Description

Return a cyclic redundancy checksum for each element in the argument.

### Usage

    cksum(a)

### Arguments

`a` | coerced to character vector

### Details

`NA`'s appearing in the argument are returned as `NA`'s.

The default calculation is identical to that given in pseudo-code in the ACM article (in the References).

### Value

numeric vector of the same length as `a`.

### Author(s)

Steve Dutky sdutky@terpalum.umd.edu

### References

Fashioned from `cksum(1)` UNIX command line utility, i.e., `man cksum`.

Dilip V. Sarwate (1988) Computation of Cyclic Redundancy Checks Via Table Lookup, Communications of the ACM 31, 8, 1008–1013.

### See Also

`bitShiftL`, `bitAnd`, etc.

### Examples

       b <- "I would rather have a bottle in front of me than frontal lobotomy\n"
     stopifnot(cksum(b) == 1342168430)
     (bv <- strsplit(b, " ")[[1]])
     cksum(bv) # now a vector of length 13

[Package bitops version 1.0-6 Index]