Newbie question on parameterized-declaration-list

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1

In the example at Derived Types — Fortran Programming Language

 type, public :: t_matrix(rows, cols, k)
   integer, len :: rows, cols
   integer, kind :: k = kind(0.0)
   real(kind=k), dimension(rows, cols) :: values
 end type

It seems to me “k” is defined as a real type, so what does the use of “integer” mean at:

   integer, kind :: k = kind(0.0)

?

2

@someknowit ,

Note that in Fortran the type of the KIND parameter itself is integer.

So place aside the parametrized derived type for now, say you wanted to declare a kind of REAL type that has a precision of at least 18: the language then suggests you can do something along the following lines:

integer, parameter :: RK_18 = selected_real_kind( p=18 )
real(kind=RK_18) : : x

So just as the type of RK_18 is an integer here even though the type of interest is REAL, the same applies in your PDT case with type parameter k.

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