我现在有一个紧迫的问题:在现代 Fortran 中声明双精度实数的公认"方式是什么?按照从最旧到最新的顺序，故事似乎是这样的:DOUBLE PRECISION，然后是 REAL(kind=8)，然后是 INTEGER, PARAMETER :: dp=kind(1.d0) 和 REAL(kind=dp)--Metcalf 现在说 dp=kind(0.d0)--现在 float32=selected_real_kind(6,37) 或 float64=selected_real_kind(15,307).所以...
Have this burning question on my mind right now: What is the "accepted" way to declare double precision real in modern Fortran? In order from oldest to newest, the story seems to go like this: DOUBLE PRECISION, then REAL(kind=8), then INTEGER, PARAMETER :: dp=kind(1.d0) with REAL(kind=dp)--Metcalf now says dp=kind(0.d0)--and now float32=selected_real_kind(6,37) or float64=selected_real_kind(15,307). So...
我个人现在写
use, intrinsic :: iso_fortran_env其中包含int32、real64等参数，含义很明显，可以这样使用:
which includes parameters such as int32,real64 which have the obvious meanings, and can be used like this:
real(real64) :: a_64_bit_real_scalar请注意，标准不保证 kind=8 提供 8 字节的种类.kind 参数采用的值不是标准化的，并且因编译器而异.
Note that kind=8 is not guaranteed, by the standard, to deliver an 8-byte kind. The values that kind parameters take are not standardised and do vary from compiler to compiler.
如果需要，您可以编写诸如
You could, if you want, write statements such as
use, intrinsic :: iso_fortran_env, dp=>real64 ... real(dp) :: a_64_bit_real_scalar