g02jgf combines output from multiple calls to
g02jff or
g02jcf.
Let
and
denote two sets of data, each with
variables and
and
observations respectively. Let
and
denote two sets of communication arrays constructed by
g02jff or
g02jcf from datasets
and
respectively. Then, given
and
,
g02jgf constructs a set of communication arrays,
, as if a dataset
, with
variables and
observations were supplied to
g02jff or
g02jcf, with
constructed as
Splitting, and then recombining, the data in this manner allows for datasets with an arbitrarily large number of observations (
) to be analysed and the preprocessing routines,
g02jff or
g02jcf, to be run in parallel.
It should be noted that, while the information in
, should be consistent with the information in the communication arrays obtained by supplying
to
g02jff or
g02jcf, the ordering of that information may change. In practice, this means that whilst an analysis run using a set of communication arrays constructed using
g02jgf should give similar results to an analysis run using a set of communication arrays constructed directly from
g02jff or
g02jcf they will not necessarily be identical. In addition, the order of the parameter estimates,
and
may differ.
None.
If on entry
or
, explanatory error messages are output on the current error message unit (as defined by
x04aaf).
Not applicable.
Background information to multithreading can be found in the
Multithreading documentation.
The data preprocessing routines,
g02jcf and
g02jff return the quantities,
fnlsv,
nff,
rnlsv,
nrf and
nvpr. These values are data dependent and, therefore, the values obtained when preprocessing the datasets,
and
are likely to be different to those obtained if you had preprocessed the combined dataset
. In order to obtain these values for
you can call
g02zlf after the call to
g02jgf. Valid values for
optstr are:
- FNLSV, in which case g02zlf will return fnlsv for the combined dataset .
- NFF, in which case g02zlf will return nff for the combined dataset .
- RNLSV, in which case g02zlf will return rnlsv for the combined dataset .
- NRF, in which case g02zlf will return nrf for the combined dataset .
- NVPR, in which case g02zlf will return nvpr for the combined dataset .
This example fits a random effects model to a simulated dataset. The dataset is split into four blocks, with
,
and
observations respectively. Each block is read in, processed by
g02jff and then combined using
g02jgf. Once all four blocks have been processed the model is fitted using
g02jhf and the results are printed.