R: Generates a deterministic checksum for an R object

getChecksum {R.cache} | R Documentation

## Generates a deterministic checksum for an R object

### Description

Generates a deterministic checksum for an R object such that (i) if the same object is used again, then the same checksum is obtained, and (ii) if another object is used, then a different checksum is obtained with extremely high probability. In other words, it is highly unlikely that two different objects have the same checksum.

### Usage

    ## Default S3 method:
    getChecksum(object, ...)

### Arguments

`object` | The object for which a checksum should be calculated.
`...` | Additional arguments passed to `digest`.

### Details

Because `getChecksum()` is a generic function, it is possible to provide custom methods for specific classes of objects. This means that, if a certain class specifies fields that carry auxillary data, then these can be excluded from the checksum calculation. For instance, assume that all objects of class 'TimestampedObject' contain timestamps specifying when each object was created. Then a custom `getChecksum()` method for this class can first drop the timestamp and then call the default `getChecksum()` function.

### Value

Returns checksum represented as a `character` string.

### Author(s)

Henrik Bengtsson

### See Also

Internally, the `digest` method is used to calculate the checksum.

[Package R.cache version 0.13.0 Index]