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List to grid reference..
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| brianbasquille@gmail.com 2006-05-01, 7:03 pm |
| Bit of a simple question here, i'd say!
Say i have a list containing two numbers ( e.g [1,2] ). How do i simply
convert this to (1,2)? To show a grid reference.
I know how to convert it the opposite way - i.e (1,2) to [1.2] is done
like so: (X,Y) = [X,Y].
... where X = 1, Y = 2. This will work without problems but when i try:
[X,Y] = (X,Y).
This won't work.
PS - am using SWI-Prolog.
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| Nick Wedd 2006-05-02, 8:02 am |
| In message <1146500637.376587.267430@y43g2000cwc.googlegroups.com>,
brianbasquille@gmail.com writes
>Bit of a simple question here, i'd say!
>
>Say i have a list containing two numbers ( e.g [1,2] ). How do i simply
>convert this to (1,2)? To show a grid reference.
I don't understand the question (and judging from the lack of response,
others don't either).
What kind of thing do you think (1,2) is? Technically it is a term
whose principal functor is a comma, and with two arguments, which could
more clearly be written ,(1,2). But I suspect that is not what you
mean.
>I know how to convert it the opposite way - i.e (1,2) to [1.2] is done
>like so: (X,Y) = [X,Y].
I don't see how that could work. Can you show us it working in context?
And when you say [1.2], do you mean it, or is it a typo for [1,2]?
>.. where X = 1, Y = 2. This will work without problems but when i try:
>[X,Y] = (X,Y).
>
>This won't work.
[X,Y] = (X,Y)
and
(X,Y) = [X,Y]
should have exactly the same effect (and that effect is not likely to be
what you want).
Nick
--
Nick Wedd nick@maproom.co.uk
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