Subversion Repositories wimsdev

# checkfor a stray '+' or '-' sign as operator.
# Do your own calculations !
# if this is true there is a small P3 penalty
# and the exercise will be returned for correction
# EVEN in Exam/Test exam mode !!

# but an answer like 1+3000*sqrt(50) should ofcourse be Ok
# and if $varlist is not empty, we should skip this test anyway
# (3+4x) is a sound answer...
# this file must be called by another procfile
# it expects a variable called AAA which is a already modified/filtered
# student answer reply$n 
# this checking is not really foolproof see below.
goback=0
errortext=$empty
!if $varlist = $empty
    !if (+ isin $AAA) or (- isin $AAA)
        dingen=i,sqrt,cos,tan,abs,log,ln
        # 'sin' 'pi' is covered by 'i'
        !for r in $dingen
            !if $r isin $AAA
                # no need to go on: 5+3*sqrt(2)+i is a good answer
                # and it is too expensive to scheck "in" the sqrt() for calculations
                !goto READY1
            !endif    
        !next r
        nummers=0,1,2,3,4,5,6,7,8,9
        !for s in +,-
            t=!positionof char $s in $AAA
            !if $t != $empty
                !for p in $t
                    t1=!char $[$p-1] of $AAA
                    t2=!char $[$p+1] of $AAA
                    !if ($t1 isitemof $nummers) and ($t2 isitemof $nummers)
                        maxscore=$[$P3*$maxscore]
                        errortext=!record 14 of $remarkdir/commonremarks.$taal
                        goback=1
                        !exit
                    !endif
                !next p
            !endif
        !next s
    !endif     
!endif

!exit

:READY1

##################################
# we could check for calculations 
# within parenthesis like this:
# (not cheap !)
#
# AAA=((1+4x)*(sqrt(2+4)))
#
# aaa=!replace internal ( by , in $AAA
# aaa=!replace internal ) by , in $aaa
#
# now aaa == ,,1+4x,*,sqrt,2+4,,,
# may be get rid of extra ,,,  first
# 
#
#
# t=!itemcnt $aaa
# !for r=1 to $t
#       chk=!item $r of $aaa
#       chk2=!charcnt $chk
#       !if $chk2 >3
#               !for x in $varlist
#                   !if $x notin $chk
#                      check on +-*
#                   !endif
#               !next x
#       !endif
# !next r