Tag Info

Hot answers tagged

8

You should be able to use the Arrow At End symbol from the Symbol Selector to show the digitised direction of polylines.


5

Since you mentioned that are you doing network analysis, I recommend assigning the symbology for your road edges within the network dataset layer in the TOC instead. You are on ArcGIS 10.2, so here are the steps: Add the network dataset into the ArcMap TOC. Open the Layer Properties dialog box by double-clicking the network dataset layer in the ArcMap ...


4

Why don't you digitalize the discrete points given in the map? The value beneath the point should be the source for the isolines. If you prefer the curves, take the lowest value found inside.


4

The v.split.length function from GRASS should do exactly what you want by splitting the line into equal segments defined by the user without the need for a point layer. Here's a simple example of a straight line (it also works on non-straight and multiple lines): I added a column to calculate its length using $length in the expression: Using the ...


3

It sounds you are after automatic raster to vector conversion and the extension to ArcGIS for Desktop that does that (as mentioned in a comment by @radouxju) is ArcScan: ArcScan provides tools that allow you to convert scanned images into vector-based feature layers. The process of converting raster data to vector features is known as vectorization. ...


3

Go to Settings - Options, digitizing tab. Tick "Suppress attribute form pop-up after feature creation".


3

The result of the interpolation that you digitized is represented in classes instead of continuous values. Therefore each color represent a interval of values, something like: < 100 100 to 250 250 to 500 > 500 (Note that the limits could be inclusive or exclusive) Now, if you plan to do some algebra analysis with it, classes and categories might not ...


3

Under Settings > Options > Digitizing, Find the "Rubberband" setting, Then "Line Colour" and adjust the "Alpha Channel" on the colour chooser. I find that an Alpha value of 50 gives a nice level of transparency but of course you can tweak it as you desire:


2

This is an issue that you'll get any time you digitize based on aerial/ortho photography. Aerial photography, even if it's ortho-rectified, will have varying levels of horizontal accuracy based on what equipment and elevation model were used. I'll bet that your two sets of imagery were compiled and released by two completely different entities (ie. You ...


2

You might like to have a look at this document, which shows an example of using the Polygonizer to make a geological map. http://confound.me.uk/maps/ppv4.pdf‎ After some recent problems, in my version of QGIS (2.3.0-Master, from Ubuntugis) the Polygonizer is now working again. Search for 'Polygonize' in the Processing Toolbox. N.


2

Finding the "right" projection is a rather time-consuming process. The best way would be to ask the map creator (if he still lives), but I guess this is not the answer you want. So take a look at available map projections, e.g. at http://www.radicalcartography.net/index.html?projectionref, and compare the shape of the degree grid with your example. At ...


1

Scan the map to xxx format and add the map to ArcGIS (sounds like you have it in jpg already). Use the Georeferecning Tools to get the map in the correct location using ancillary data. A good time to set the projection. Create empty point, line, and polygon Feature Classes. Using the Editing Toolbar to digitize your features into the files Add required ...


1

ArcScan is meant to digitize drawings (typically scanned cadastral maps or the likes). In your case you want to classify an RGB image. With a true color image, you can use the image classification toolbar . You'll need to draw some sample polygons and use them for training a classifier. You need spatial analyst licence for that, and I would rather use an ...


1

As long as you 'drew' the lines from upstream to downstream in a consequent fashion, you can do this through the styling options. Right-click the shapefile layer, select Properties. Then select 'style' from the left hand side menu. Where you set the linestyle, on the top right you can choose a symbol line. Then you can select which symbol (I used the ...


1

@Mapperz suggested I configure my tablet not to response to double click. I tried doing this but the features were non-responsive. It seems that the Pen and Touch and default windows tablet features and services are taking over some of the Wacom Intuos functionality. After I turned of the Table PC Input Services and then Tablet PC Component Features and ...


1

You can snap a line to itself, but only after saving. My workaround is to digitize the line, but set the last point a bit offset to the first point, then save, and then move the last point to the first. As a consequnce, I start digitizing a new closed line with a point that is already created by another adjacent polygon if possible.


1

Go to Settings -> Options. In the Options menu go to the Digitizing tab, then adjust your rubberband color. Drop your alpha channel value down, by default it is 200, the lower it is set the more transparent your digitized polygon will be as you build it. For me 50 was a good setting. If you set it too low you won't see anything at all. When I was ...



Only top voted, non community-wiki answers of a minimum length are eligible