My previous comment about being impressed with the overlay of 2 polygon
files related purely to the fact that it didn't crash. I was not impressed
at all with the speed. The fact that an earlier corrspondent found it faster
to export to another package, do it there, and import back to MI is hardly
surprising, given the hours I wait for tasks of any significant size.
I'm glad to hear (sort of) that someone else also had problems with
buffering into the cosmetic layer. I've also found that when "erase outside"
fails, sometimes it works when you split the target first, and then erase
outside.
MI's poor topology would have to be its major weakness. Mapcheck.mbx is
good, it tells you where the topological errors are, but isn't that just
rubbing salt into the wound when you can't do anything to fix it? Yes, you
can do it manually, but that becomes unfeasible with larger datasets. The
ability to clean datasets and build correct topology is just fundamental to
GIS, and until MI can do this, its users will always be reliant on being
provided with good, GIS-ready datasets, or using other packages as well to
fill this gap.
If some of these basic functions were more satisfactory, then I would be
pleased to turn my attention to things like obscure button combinations
causing crashes.
Regards
Peter Walsh
Dames & Moore
email: [EMAIL PROTECTED] <mailto:[EMAIL PROTECTED]>
Ph. +61 (2) 9955 7772
"This e-mail is intended only for the use of the individual or entity
names above and may contain information that is confidential and
privileged. If you are not the intended recipient, you are hereby
notified that any dissemination, distribution or copying of this e-mail
is strictly prohibited.
If you have received this e-mail in error, please notify us immediately
by return e-mail or telephone + 61 2 9955 7772 and destroy the original
message. Thank you."
> -----Original Message-----
> From: Steve Wallace [mailto:[EMAIL PROTECTED]]
> Sent: Friday, 20 August 1999 1:37
> To: [EMAIL PROTECTED]; MapInfo Discussion Group (E-mail)
> Subject: Re: MI trouble combining complex polygons
>
>
> I don't mind the processing speed. In fact, some of the
> object functions
> have sped up. But the speed is of no benefit if the topology
> is worthless.
>
> The changes they have made in object processing are for the
> better. But they
> need to fix the problem of how MapInfo 5.5 creates buffers
> into the cosmetic
> layer. If you haven't tried it, MI creates anything from
> ovals to flat lines
> when buffering points into the cosmetic layer.
>
>
> Steve E. Wallace
> GIS & Market Information Manager
> Florida Farm Bureau Insurance Companies
> ----- Original Message -----
> From: Tony Elson <[EMAIL PROTECTED]>
> To: MapInfo Discussion Group (E-mail) <[EMAIL PROTECTED]>
> Sent: Thursday, August 19, 1999 9:31 PM
> Subject: Re: MI trouble combining complex polygons
>
>
> >
> >
> > Peter Walsh wrote:
> > >
> > > I was impressed with 5.5 when it overlayed 2 complex
> polygon sets that I
> > > knew would have failed in previous versions, with the
> dreaded "regions
> too
> > > complex" message. I fairly quickly discovered however
> that it still has
> its
> > > limitations, beyond as certain point it still just fails.
> It doesn't
> give
> > > you an error message, it just doesn't do anything.
> > >
> > > You could try copying them both into a base table, and
> trying htere,
> rather
> > > than in the cosmetic layer. I don't know if this will
> work, but I have
> > > noticed the buffering function sometimes seems to be more
> successful if
> I
> > > don't use the cosmetic layer, but rather save the results
> straight into
> a
> > > table.
> > >
> > > The only solution regarding complex datasets for me has
> been to work in
> > > grids, and the speed at which Vertical Mapper can create grids,
> maipulate
> > > them, and contour them back into vectors is impressive.
> Inevitably, some
> > > resolution is lost.
> > >
> > > If you want to work in vectors, it seems the only answer is to buy
> something
> > > better than a desktop GIS.
> > >
> >
> >
> >
> > Personally, I have found MI's combine objects function to
> be a bit of a
> > dog. Way to slow (which may have something to do with my underlying
> > data structure).
> >
> > It was quicker for me to export the data set(s) via UT and do my
> > processing in ArcView. The geo-processing tools in AV are far more
> > advanced, easy to use and just that much faster.
> >
> > A personal opinion only, but I would be interested in reading some
> > others' comments on MI's geo processing because my experience is
> > admittedly limited, which could therefore cause my vision to be rose
> > coloured.
> >
> >
> > Regards
> >
> >
> > -----------------------------------
> > Tony Elson
> >
> > GIS Analyst
> >
> > Geographic Technologies Limited
> > PO Box 6015
> > Wellesley Street,
> > Auckland, New Zealand
> >
> > Ph: 64 9 379 2061 x107
> > Fax: 64 9 379 2044
> > Mobile: 025 278 4896
> > Email: [EMAIL PROTECTED]
> > [EMAIL PROTECTED]
> > ------------------------------------
> >
> ----------------------------------------------------------------------
> > To unsubscribe from this list, send e-mail to
> [EMAIL PROTECTED] and put
> > "unsubscribe MAPINFO-L" in the message body, or contact
> [EMAIL PROTECTED]
>
>
>
>
> ----------------------------------------------------------------------
> To unsubscribe from this list, send e-mail to
> [EMAIL PROTECTED] and put
> "unsubscribe MAPINFO-L" in the message body, or contact [EMAIL PROTECTED]
>
----------------------------------------------------------------------
To unsubscribe from this list, send e-mail to [EMAIL PROTECTED] and put
"unsubscribe MAPINFO-L" in the message body, or contact [EMAIL PROTECTED]
