# 194. Use PACK to select records from an array of derived types.
topic: {ref}`derived-types`
```{note}
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```
With an array of derived types, you can use PACK with a MASK on type components to select records, for example
type :: t
integer year, month, day
real x
end type t
type(t) :: d(1000)
print*,pack(d, d%month==3) ! data for March
@carbon_app
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