Fortran :Operand of .not. operator at(1)is REAL(4)

1）报错信息

DO WHILE (.NOT.EOF(IUNAG))

Error:Operand of .not. operator at(1)is REAL(4)

2）问题分析

fortran标准里没有eof函数

eof确实识别成了real

3）问题解决

采用类似这个方式来进行：

read(unit, *, iostat = io_status) number

program read_file
    implicit none
    integer :: unit, i, io_status
    real :: number
    unit = 10  ! 文件单元号
    open(unit, file = 'data.txt', status = 'old')
    do
        read(unit, *, iostat = io_status) number
        if (io_status < 0) then
            print *, 'End of file reached.'
            exit
        end if
        print *, number
    end do
    close(unit)
end program read_file

4）