Software

Using a highly interactive system (cont'd)

Using a general-purpose high-level programming language

Operating systems need to be very robust

Using a report-generation language

If a programme is written in a language which ‘knows about’ the record structure, it won't be necessary to modify the code when the record structure changes.

TOTAL_WEIGHT = 0; NUMBER = 0
REPEAT
  [ READ_NEXT_RECORD
    IF(END_OF_FILE) BREAK
    IF("AGE" >= 18. AND "SEX" = 'F')
      [ TOTAL_WEIGHT = TOTAL_WEIGHT + "WEIGHT"
        NUMBER = NUMBER + 1
       ]
   ]
AVERAGE_WEIGHT = TOTAL_WEIGHT / NUMBER
PRINT 'Average weight = ', AVERAGE_WEIGHT
END

R. Funnell

Last modified: Thu, 2007 Mar 15 08:35:42

Slide show generated from sw.html by Weasel 2007 Mar 15