Fortran分割讀取字符串數字混合文本行

利用函數index:

INDEX(STRING,SUBSTRING,BACK)

purpose: return the starting position of a substring within a string

               When BACK missing or BACK=.False. , return the first starting postion of substring, if no substring in string or LEN(string)<LEN(substring), return 0, if LEN(substring)=0, return 1 ;

 　　　　When BACK=.True., return the last starting position of substring. The return value is similar as .False. case.

 

EXAMPLE: 文本文件

                xyz   x   1   y   2   z   3

　　　　分割提取字符和數字

program main
    implicit none
    character(len=100) :: str
    integer :: x,y,z,id
    character(len=3) :: xyz
    
     read(*,'(a)')  str
     id=index(str,'xyz',BACK=.False.)
     xyz=str(id:id+2)
     str(id:id+2)=''
     id=index(str,'x')
     x=str(id)
     str(id)=' '
     id=index(str,'y')
     y=str(id)
     str(id)=' '
     id=index(str,'z')
     z=str(id)
     str(id)=' '
     read(str,*) x,y,z

end program main