[QTI] tolerance attribute in equal expression

[Marina Zelwer]

Thanks a lot for your answer.
What made me think that the tolerance attribute should appear twice when 
whe want two different values for t0 and t1 is the cardinality :
"Attribute : tolerance [0..2]"
given in the documentation.

regards
Marina

Steve Lay wrote:
> At 15:49 +0200 2006-05-19, Marina Zelwer wrote:
> 
>>I've got a problem with the tolerance attribute of the equal expression
>>(QTI2.1). If I understoud the documentation, if I want a tolerance like :
>>[x-t0,x+t1]
>>the tolerance attribute has to appear twice, once for the value of t0
>>and once for the value of t1.
> 
> 
> Firstly, if t0 and t1 are the same then you can give it once only and
> you're done.  "If only one value is given it is used for both."
> 
> However, if you have two different values then they must both be put into a
> single instance of the tolerance attribute.  It is true that the order of
> attributes within an element is not significant in XML but the order of
> items within a space-separated attribute value is significant.
> 
> In other words:
> 
> <myElement attr1="A" attr2="B"> is the same as <myElement attr2="B" attr1="A">
> 
> But:
> 
> <myElement attr1="A B"> is not the same as <myElement attr1="B A">
> 
> The tolerance attribute uses the latter form in the binding.
> 
> What does need clarification is the fact that t0 appears first when bound.
> It is almost explicit in the names "t0" and "t1" but it should be spelt
> out: should be fixed in the next release of the documents.
> 
> Thanks for drawing this to our attention.
> 
> Steve
> 

-- 
Marina Zelwer

Centre Commun Multimédia C2M
Université Jean Monnet
2, rue Tréfilerie,
42023 Saint Etienne
Tel : 04.77.42.16.17