PROGRAM single_column
! save data in a single column
! file$ example of string variable
INPUT prompt "name of file for data? ": file$
! channel number #1 associated with file and can be passed to
! subroutines
! various options may be specified in OPEN statement
! access output: write to file only
! create newold: open file if exists, else create new file
OPEN #1: name file$, access output, create newold
! True BASIC does not overwrite data in a text file
! ERASE #1                          ! erase contents of file
! RESET #1: end   ! allows data to be added to end of file
FOR i = 1 to 4
    LET x = i*i
    PRINT #1: x                   ! print column of data
NEXT i
CLOSE #1
! channel # irrelevant if only one open at a time
OPEN #2: name file$, access input
FOR i = 1 to 4
    INPUT #2: y                   ! print column of data
    PRINT y
NEXT i
! files automatically closed when program terminates
CLOSE #2                          ! not necessary but good practice
END