needed: map with boundaries and points
gwhi...@gmail.com
and with several hundred points mapped onto it. As is usually the
case, there is no budget associated with this request. I have been
investigating various data sources and open source GIS apps (notably
QGIS)... but frankly I have not been able to bring it all together...
there are so many file types and proprietary solutions.
Would someone help me identify the 'full set' of what's needed? That
is, the proper file types or components and a (free) tool that will
display them. I believe I can figure out how to produce a CSV file of
the locations I need to map, which I gather will need to be converted
from street addresses to lat/long pairs. But what, where, and how to
find the map image itself, and an overlay for municipal boundaries,
and match them... I'd very much appresiate some guidance. Thanks in
advance. --Gary
Paul Cooper
I'm afraid you may be out of luck with free data for municipal
boundaries. These data are copyright the Ordnance Survey, and are not
normally free. You may be able to get your local authority to let you
have the data, if you have a relationship with them, but otherwise you
probably need to pay.
Shapefiles are the most common way of getting data in to pretty much
any GIS; YMMV depending on what solution you choose.
One way forward that you might like to consider would be to use
GoogleEarth, which comes with most of the data you need. It is pretty
straightforward to convert your CSV data into a KML file; you could do
it manually or with a script in your editor probably. KML is pretty
straightforward.
Paul
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Jean H
Hi Gary,
Google should be your friend! ... there are lots of map layers available
online!
From your IP address, it seems your are in NY, Greene County. Have a
look here:
http://www.nysgis.state.ny.us/gisdata/inventories/results.cfm?SWIS=19§orIDs=&themeIDs=1
especially entry #11
Download the shapefile
(https://www.nysgis.state.ny.us/secured/coop/fileserver/?DSID=927&file=civil_boundaries_shp.zip
)
Then open this file in QGis (or else), and voila!
The freeware "GVsig" might be easier to use...
http://www.gvsig.gva.es/index.php?id=1731&L=2
To geocode your points, read your GIS manual:
for QGis:
http://gisalaska.com/qgis/doc/user_guide_en.pdf p105, section 11.4
for GVsig:
http://www.gvsig.gva.es/fileadmin/conselleria/images/Documentacion/descargas/manuales/gvSIG-1_1-man-v1-en.pdf
p100, section 5.8.1
You could also use http://ofb.net/%7Eegnor/google.html to extract the
coordinates from your street address.
Now, the beauty of a GIS (versus an image editor) is that your data is
georeferenced. It means that each point or polygons has coordinates in
it, which allows the program and the user to locate the dataset on the
globe. You can also display several layers of data, one on top of each
other. So, in your case, you would display the boundary, then overlay
your point data (and any other layer such as the road network etc), and
this will automagically create a map for you, with each item loacated at
the correct place!
Hope this help!
Jean
gwhit
Thanks, Paul... I did start out with Google Earth; I'll give it
another go. -_Gary
gwhit
wrote:
> gwhit...@gmail.com wrote:
> > I need to produce a map of our County which shows municipal boundaries
> > and with several hundred points mapped onto it. As is usually the
> > case, there is no budget associated with this request. I have been
> > investigating various data sources and open source GIS apps (notably
> > QGIS)... but frankly I have not been able to bring it all together...
> > there are so many file types and proprietary solutions.
>
> > Would someone help me identify the 'full set' of what's needed? That
> > is, the proper file types or components and a (free) tool that will
> > display them. I believe I can figure out how to produce a CSV file of
> > the locations I need to map, which I gather will need to be converted
> > from street addresses to lat/long pairs. But what, where, and how to
> > find the map image itself, and an overlay for municipal boundaries,
> > and match them... I'd very much appresiate some guidance. Thanks in
> > advance. --Gary
>
> Hi Gary,
> Google should be your friend! ... there are lots of map layers available
> online!
> From your IP address, it seems your are in NY, Greene County. Have a
> especially entry #11
> Download the shapefile
> )
>
> Then open this file in QGis (or else), and voila!
>
> To geocode your points, read your GIS manual:
> for QGis:http://gisalaska.com/qgis/doc/user_guide_en.pdf p105, section 11.4
> p100, section 5.8.1
>
> You could also usehttp://ofb.net/%7Eegnor/google.html to extract the
> coordinates from your street address.
>
> Now, the beauty of a GIS (versus an image editor) is that your data is
> georeferenced. It means that each point or polygons has coordinates in
> it, which allows the program and the user to locate the dataset on the
> globe. You can also display several layers of data, one on top of each
> other. So, in your case, you would display the boundary, then overlay
> your point data (and any other layer such as the road network etc), and
> this will automagically create a map for you, with each item loacated at
> the correct place!
>
> Hope this help!
> Jean
Thanks SO much, Jean... That was precisely the sort of simple,
complete direction I needed. I've gotten the boundary shapefiles that
you pointed to (I do have access to that nygis data sharing coop) and
loaded them in QGIS just as you suggested. gvSIG is downloading as I
write this (and they have a native mac version!). It's Columbia
County, by the way.
I'm still a ways from any deliverable, but I'm not quite as *stuck* as
I was--and that is a breath of fresh air! Still to figure out: how to
get the layers to lay on top of one another--to be visible, so to
speak, rather than only the 'top' one. For instance, the town/city
boundaries on top of the County boundary on top of the county map
raster (with my points, once I get them in a shape file, on top of it
all)
That's all for tonight... thanks again! --Gary
gwhit
environs (the shapefile shows all municipal boundaries in the whole
state). thanx, --Gary
Jean H
> I was--and that is a breath of fresh air! Still to figure out: how to
> get the layers to lay on top of one another--to be visible, so to
> speak, rather than only the 'top' one. For instance, the town/city
> boundaries on top of the County boundary on top of the county map
> raster (with my points, once I get them in a shape file, on top of it
> all)
Ok, you have 3 ways of displaying a polygon: its border only, a filled
polygon only, or a filled polygon plus its barrier (default display). If
you display a point or a line over a polygon, you will see the point
and the polygon underneath. If you display several layers of polygon and
want to see every polygons in every layers, you would have to draw only
the border (except for the bottom layer, of course). Usually a right
click on the layer name + "display properties" would allow you to change
the way the polygons are displayed (read your GIS manual).
Remember that you change the order of the layers (which one is on top,
the 2nd etc), usually by dragging the layer name up or down in the list
of layers.
> Additionally, I need to limit my map to just one county and immediate
> environs (the shapefile shows all municipal boundaries in the whole
> state). thanx, --Gary
I am not too familiar with the open source GIS... so read the manual to
find out if it is possible/how to do it, but you basically have 2 options:
1) make a query (usually an SQL query) on your layer, selecting only the
entries being in your county. You may do this by querying an attribute
of your polygons, if you have any. Otherwise, you may do it by a spatial
query, selecting all the polygons (municipalities) that lay under the
polygon of your county. This option is more professional than the next one.
2) by hand, select your polygons... copy and paste in a new shapefile.
Otherwise, inverse the selection (so you get all polygon but the ones
you want) and delete them from your file!
Good luck in your project!
Jean
Gary W
raster map of the County overlaid with both county and municipal
boundaries in gvSIG... it looks good. Of course the point is to plot
locations on it, and there's the rub. I've cleaned up all the
addresses and geocoded them at batchgeocode.com, and used the
resulting csv file to produce a layer as you suggested, Jean (by the
way, to make the csv import filter work, you actually have to delimit
your fields with semicolons... it's a European thing, I guess). I've
also used another free tool (MapWindow GIS) to produce a shapefile
from that data.
The problem is, in both cases, that the resulting points end up in
South America or somewhere, so to speak. The latitude & longitude
coordinates are interpreted as (I think) meters, so something like
42.0000/-73.5000 is represented as 0.0004/-79.5000. There is some
functionality to do transformations when adding a shapefile layer, but
I'm not savvy enough with the various reference systems &/or the
software doesn't support the operation I need.
So the long and the short of it is, all the data from
nygis,state.ny.us plays nice together, but I can't integrate geocoded
lat/long data.
I'd appreciate any illumination you could provide, --Gary