updateAttributes: Update Attributes of a 'ddo' or 'ddf' Object
In datadr: Divide and Recombine for Large, Complex Data

Description Usage Arguments Details Value Author(s) References See Also Examples

Update attributes of a 'ddo' or 'ddf' object

1	updateAttributes(obj, control = NULL)

`obj`	an object of class 'ddo' or 'ddf'
`control`	parameters specifying how the backend should handle things (most-likely parameters to `rhwatch` in RHIPE) - see `rhipeControl`

This function looks for missing attributes related to a ddo or ddf (distributed data object or data frame) object and runs MapReduce to update them. These attributes include "splitSizeDistn", "keys", "nDiv", "nRow", and "splitRowDistn". These attributes are useful for subsequent computations that might rely on them. The result is the input modified to reflect the updated attributes, and thus it should be used as obj <- updateAttributes(obj).

an object of class 'ddo' or 'ddf'

Ryan Hafen

Bennett, Janine, et al. "Numerically stable, single-pass, parallel statistics algorithms.' Cluster Computing and Workshops", 2009. CLUSTER09. IEEE International Conference on. IEEE, 2009

ddo, ddf, divide

d <- divide(iris, by = "Species")
# some attributes are missing:
d
summary(d)
d <- updateAttributes(d)
# now all attributes are available:
d
summary(d)