例如：
3.140000 简化为 3.14
3.00 简化为 3
3.040 简化为 3.04
3.040e30 简化为 3.04e30
program www_fcode_cn
implicit none
character( len = 52) :: c
Do
read(*,*) c
call TrimStringNumber(c)
write(*,*) Trim(c)
End Do
end program www_fcode_cn
Subroutine TrimStringNumber( c )
!// Trim real String program
!// Fortran Coder : Gao [ gao@fcode.cn ]
!// http://www.fcode.cn
character( Len = * ) :: c
integer :: n
integer :: i , j , k
c = AdjustL( c )
n = Len_Trim( c )
i = index( c , "E" )
j = index( c , "e" )
k = max( i , j )
if ( k > 1 ) then !// 指数
j = index( c(:k-1) , "." , back = .true. )
if ( j < 1 ) return
Do i = k-1 , j+1 , -1
if( c(i:i) /= '0' ) exit
End Do
if ( i /= j ) i = i + 1
c(i:n) = c(k:n)
else !// 常规小数
j = index( c , "." , back = .true. )
if ( j < 1 ) return
Do i = n , j+1 , -1
if( c(i:i) /= '0' ) exit
End Do
if ( i /= j ) i = i + 1
c(i:n) = ' '
end if
End Subroutine TrimStringNumber
