在Fortran中USE语句应该放在哪里?

Question

我正在为我的第一个Fortran项目制作一个物理计算器。我已经有了速度/距离/时间部分，它实际上运行得很好。然而，当我试图添加电流，充电和时间模块时，我遇到了一个问题-我在哪里为我的模块放置USE语句?代码如下:

module kinematics
implicit none
real :: t, d, s
contains
subroutine time_from_distance_and_speed()
print *, 'Input distance in metres'
read *, d
print *, 'Input speed in metres per second'
read *, s 
t = d / s
print*, 'Time is ', s 
end subroutine
subroutine distance_from_speed_and_time()
print *, 'Input speed in metres per second'
read *, s
print *, 'Input time in seconds'
read *, t 
d = s * t
print*, 'Distance is ', d
end subroutine
subroutine speed_from_time_and_distance()
print *, 'Input distance in metres'
read *, d 
print *, 'Input time in seconds'
read *, t 
s = d / t
print *, 'Speed is ', s
end subroutine
end module
module electronics 
implicit none
real :: Q, I, T 
contains
subroutine charge_from_current_and_time()
print *, 'Input current in amps'
read *, I
print *, 'Input time in seconds'
read *, T 
Q = I * T
print*, 'Charge is ', Q 
end subroutine
subroutine current_from_charge_and_time()
print *, 'Input charge in coulombs'
read *, Q
print *, 'Input time in seconds'
read *, T 
C = Q/T
print*, 'Distance is ', d
end subroutine
subroutine time_from_current_and_charge()
print *, 'Input current in coulombs'
read *, Q 
print *, 'Input charge in amps'
read *, I 
T = Q/I
print *, 'Speed is ', s
end subroutine
end module
program bike
integer :: gg
integer :: pp
print *, 'Press 0 for speed, distance, and time. Press 2 for current, charge and time.'
read *, pp
if ( pp == 0 ) then
do while(.true.)
print *, 'Press 1 for speed, 2 for distance, and 3 for time'
read *, gg
if(gg == 1) then
call speed_from_time_and_distance
else if(gg == 2) then
call distance_from_speed_and_time
else if(gg == 3) then
call time_from_distance_and_speed
end if
print *, 'Press 5 to exit the console, or press 4 to do another calculation'
read *, gg    
if(gg== 5) then
exit
end if
end do
end program

Answer 1

use语句放在每个编译单元(模块、程序或过程)的开头，在program、module、function或subroutine行之后，在任何implicit语句或声明之前。(你应该在每个模块和每个程序中都有implicit none)

对于非常短的程序，如果你省略了program bike，你可以直接从use语句开始。