# Setting covariate grouping levels:

## !FACPOINTS and !POLPOINTS

The fac()
and pol() model terms need to classify a covariate
into discrete classes. This is usually done on the basis of
unique covariate values. However, ASReml will actually consider
close points as being the same. This is controlled by

!FACPOINTS `n `
affects the number of distinct points
recognised by the fac() model function. The default value of
` n` is 1000 so that points closer than 0.1% of the range are
regarded as the same point.
!POLPOINTS `n `
affects the
number of distinct points recognised by the pol() model
function. The default value of ` n` is 1000 so that points closer
than 0.1% of the range are regarded as the same
point.
## Example

One use of facpoints is in association with fac(dam,year)
used to define a concise interaction of dam
and year, where there are more than 1000 dams.
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