>
>I was about to try to draw a map of about 100,000 axiallines to be processed
>on axman when I read Alan's message, is this limit for processing only or
>also for display? and it is only processing do you think that Orange box can
>handle more than 32,000??
Well it can and it can't, I belive you can physcially view and process
such a
number of axial lines in Axman, how ever the ID numbers (Identifer
Numbers )
wrap around at 32,000. For Small Aixal models when you are assigning
flows
to people you need to know which is line 223 and 225. For the ultra maps
numbering
each axial line indervidually is not normally useful.
>Also how can I get information about Ovation software? and can someone
>direct me to information on the use of space syntax in the field of GIS and
>the opposite?
I wrote Ovation and sold the rights to it to Space Syntax Ltd, so you
will need
to contact them for a copy/support. Before you get too happy it's Mac
software again.
On the plus side you will find that you can process vast maps with it ( I
belive
Syntax used it to process the nearly complete map of Tokyo with numbered
in
the millions of axial lines ).
The big advantage of Oviation is you can process maps which where
digitiesed in a GIS
system where there is typically a geomatic encodeing ie you get
coordingates like
100202043.000001 , 30232.00001
100202043.0000021, 30232.000021
100202043.0000076, 30232.00009
100202043.0000087, 30232.00008
100202043.0000089, 30232.00005
100202043.0000045, 30232.00003
100202043.0000034, 30232.00002
100202043.0000023, 30232.00001
ie huge offsets (for lat/longitude), + tiny tiny tiny units for the city
position
The real problem which came out testing Ovation was that you must be
quite an
expert to use a GIS system. Ovation is like oranage box (really really
really fast),
how ever it still assumes that lines are being intersected on a plane. A
real
city actually is spread over a sphere ( the earth ), and as such the
lines are
bent into a spherical coordinate system. Normally the approximation
between both
spherical and planar coordiantes are minimal, how ever digitising in a
gis may
or may not be in the spherical coordinates ( which you normally set up
before digitising), for large cities you may not get perfect
intersections when computing them in Ovation.
As always with disconections this may not be important or it may be
absolutely vital.
For GIS pro's this is not a problem - just convert from polar to planare
coordinates with an
affince transform.
hope this helps.
sheep
>Thanks,
>
>Mohamed Salheen
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