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5

You could use the freely available Level 2 GADM shapefile data for Greenland, which comes in EPSG:4326 (Lat/Lon projection) by default, and import it into R using the GDAL functionalities offered by the rgdal package. Then, define the geographic extent for Washington Land and crop the previously imported shapefile. Make sure you have all the required ...


3

Why not just use county shapefiles from the Census Bureau? The Census recognizes those independent Virginia cities as both cities and as independent counties for the purposes of geographic distinction. Here is a list of the areas designated at the county level by the Census Bureau for the state of Virginia. You can find shapefiles for all counties here.


3

there are a few examples on this site, like the maps of Africa and USA below. Also one map here and here Also note that in the first days of digital image analysis, raster images where printed with ascii caracters (one caracter per value). This was not really "art", but it was the only way to visualise (on screen or on paper) a raster when screens and ...


3

it seems you can use a &z=nn parameter now Try this: <iframe src="http://mapsengine.google.com/map/u/0/embed?mid=zYk_BmXXTdxw.k83snDbX5SJc&z=9" width="745" height="480"></iframe>


2

Adding another layer with some markers and making invisible worked perfectly for me. You can keep the new map style too with custom markers etc!


2

One presumes you are already familiar with Section508.gov but those who may find this later may not be. For general accessibility resources see The Accessibility Project although that is primarily focused on web accessibility. For more cartographic specific accessibility tests consider the Colour Contrast Analyser and Vischeck.


2

Unfortunately the answer to many of your questions is tied into the history of the USGS mapping program and decisions made, reversed, and reimplemented along the way. I don't know the specifics for that exact scale option, nor a more current version of the resource mkennedy mentions. I stumbled across a pdf earlier from I thought 2011 where a USGS official ...


2

3D is not (yet) implemented in QGIS, but you can store the height in an attribute table field and create a 3D output manually with ogr2ogr -z_field fieldname outside QGIS. See Is it possible to create 3D dxf with OGR? for an example. This is rather 2.5D, because all vertices of a line must have the same elevation (as contours have). In QGIS, you could use ...


2

I don't see why ASCII Art should be unsuitable for Cartography. Art subjects can range: from the most common such as people and landscapes; to the outright ridiculous like a toilet or an unmade bed (that's Modern Art for ya!). In terms of ASCII Art, maps can be drawn fairly accurately. Just depends on the resolution required and the amount of time ...


2

The actual answer is a mixture of the other answers/comments you've already received. MySQL is limited I see from the tags you're using MySQL, the problem is, it can only do bounding boxes until 5.6, not the actual geometries. http://dev.mysql.com/doc/refman/5.0/en/spatial-relation-functions.html If you want to use the bounding box: SELECT * FROM `test` ...


2

From the longitude and latitude coordinates, you can create spatial structures (Points) in your (spatial) database, like PostGIS. (see ST_GeomFromText) Instead of your bussId | longitude | latitude, you would have a bussId, Point database called BussSpatial. You can then just query the following var request = 'SELECT bussID FROM BussSpatial ...


2

leaflet does support onmouseup event. i just used your code and modified a bit to remove eventListener on mouseup. now it's working fine even if you pan your map. circle.on({ mousedown: function () { map.on('mousemove', function (e) { circle.setLatLng(e.latlng); }); } }); map.on('mouseup',function(e){ ...


2

My usual method is to use the convert utility from either ImageMagick or GraphicsMagick to convert a sequence of still images from a variety of formats, including PostScript, and output a variety of other formats, such as an animated GIF or MNG. For example, from a directory with several PostScript files, make an animated GIF with 0.2 seconds between each ...


2

Model builder, to my knowledge, does not expose the data driven pages functionality that you access on the toolbar. If you want to automate map output with data driven pages then you must use python and arcpy. Search help for DataDrivenPages (arcpy.mapping). From this page there is also a link to building map books.


1

If those "strange" coordinates do not fit to Gauss-Krueger coordinate systems, they might be similar to the "preußisches Koordinatensystem". You will find some links to that in my answer to Conversion of coordinates of "Bochum coordinate system" You have to put up a custom CRS on the point "Trockenberg" in Cassini-Soldner projection, which was ...


1

I assume you know of a project in QGIS (the QGS file) like SecludedPath suggests. If you (on Windows) save a project in the folder C:\Users\USERNAME.qgis2\project_templates. It will be available in the menu Project > New From Template > your project. If you want to quick access for using that project as a starter for a new project.


1

There is no way you can get the map that small and still be readable like at that zoomlevel. Just consider this: the scalebar on gmaps (bottom right corner) is roughly 1", so even at z14: 1 km = 1 inch an imaginary country with 1000km*1000km, so a map of that country would take 1000"x1000" (1000000) you want it colored, so at least 8bit, i.e. *8 you want ...


1

You need to update your paths in the zoomed function. The original example does this on line 68. The simplest thing to do is to use the counties variable store a reference to the selection of paths: counties = topojson.feature(us, us.objects.barrios); counties = svg.selectAll("path") .data(counties.features) .enter() .append("path") ...


1

To make a circle draggable, you can add an event listener with a method for mousedown and one for click (from what I've seen, Leaflet doesn't support mouseup for Path layers). Inside the mousedown event, add a function to get the position of the circle from the current mouse position. Inside the click event, remove the previous event listener to make the ...


1

To create a NDVI image you need to use the channels for red and near infrared (NIR) reflectance. The red channel is usually in a wavelength range between 0.6-0.7µm and the near infrared channel in a range between 0.7-1.10µm. So if one of your 6 files is in one of these widths you can use it for the calculation. In QGIS there are two ways to calculate the ...


1

Have a look on the documentation here : http://docs.qgis.org/2.6/en/docs/user_manual/print_composer/print_composer.html#atlas-generation and the example in http://nathanw.net/2014/09/23/qgis-atlas-on-non-geometry-tables/


1

Try the ArcGIS SDK for Android: Get the SDK that lets you build native mapping apps for Android devices! Integrate a wide range of mapping and GIS tasks online or offline, including editing, geocoding, routing, mapping, and data visualization.


1

The bounding box query for SQL is(Using PDO) $sql ="SELECT bussid FROM tablename WHERE(latitude BETWEEN ? AND ? )AND (longitude BETWEEN ? AND ?)"; $stmt = $dbh->prepare($sql); // Assign parameters $stmt->bindParam(1,$minLat); $stmt->bindParam(2,$maxLat); $stmt->bindParam(3,$minLng); $stmt->bindParam(4,$maxLng); WHERE parameters come from ...


1

I think your problem is related to this question, this answer and this bl.ock. at least one issue is that you haven't defined #infowindow_template, but you can get a simple onclick popup of the country name by adding the following: cdb.vis.Vis.addInfowindow(map, layer.getSubLayer(0), ['name']); in place of: sublayer.infowindow.set('template', ...


1

I found the problem, I added ol.interaction.Select({condition:ol.events.condition.mouseMove}) which prevents map dragging. The vector-layer.html example solves navigation issue with mouseover interaction


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When you are writing your SQL query after importing the USA dataset (as Javier referenced above), be sure to select 1) "the_geom", 2) "the_geom_webmercator", and 3) "cartodb_id". See my code underneath: SELECT ne_50m_admin_1_states.the_geom, ne_50m_admin_1_states.the_geom_webmercator, ne_50m_admin_1_states.cartodb_id FROM ne_50m_admin_1_states WHERE ...


1

This is a link to Google's documentation on how to allow users to draw polygons and other shapes on a map: https://developers.google.com/maps/documentation/javascript/drawinglayer The basic steps are: Add a drawing tool to the map. https://developers.google.com/maps/documentation/javascript/examples/drawing-tools Add a listener event for when the ...


1

solved It: function calculateArcPointsGeo(center, radius, startAzimuth, endAzimuth, segments) { var pointList = [], point, i, d = radius / 1000, // d = distance in km R = 6371, // km, R = earth's radius (mean radius = 6,371km) lat1 = deg2Rad(center.Y), lon1 = deg2Rad(center.X), ...


1

Not a complete answer! I don't know how to identify what areas had 1:25,000 mapping done. You might try searching the Federal Register based on the information below. USGS published Maps for America (3rd edition, 1987) by Morris M. Thompson. On page 109, it states "By 1978, published 1:24,000-scale topographic maps were available for about 70 percent ...


1

colorbrewer will address colorblindness: http://colorbrewer2.org/ for web based, best bet is too follow w3c standards: http://www.w3.org/TR/WCAG20/ for native, you should reference the operators site, for example, i know ios a11y information is up on apple's site, and the same for microsoft



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