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8

There is no need to manually digitize all the OSM Maps. According to the OSM website OpenStreetMap is a map of the world, created by people like you and free to use under an open license. So you are able to use the underlying data in all the maps, Simply download what you want to use, following the steps in this guide or this one.


6

I'm assuming you want to automatically populate the field with the date at which the feature was edited - apologies if this is not correct. Create the shapefile and add a field in the attribute table in which to store the date - you should be able to specify "date" as the type of input. Add the shapefile into QGIS and then open its properties. Under the ...


5

Not at all. When you have some data that was digitized at 1:100,000, it excluded smaller features, which were smaller than the Minimum Mappable Area. For example, suppose you are dealing with topographic data.At 1:100,000 you would exclude large streams and trees.These features are visible at 1:24,000, and should be included in such a map. If you just ...


4

You can create a new field with the field calculator and write the current date with a simple SQL command. Open the Layer properties Enable editing open field calculator Create a new field using now from the date and time section of the functions This creates the current date on the new attribute. If you need to write the current date every time you ...


4

It looks like you solved the issue, but as I had the same issue I'd like to elaborate. My issue was with a shapefile created in Arc and edited in QGIS. All edits appeared to be taking during the edit session, but new features would disappear when saved. Any features that were modified rather than created would render correctly. The records were present in ...


4

Create nice unique id for lines Convert them to 3d using interpolate shape tool Create field fromZ in above. Use field calculator to populate it, parser Python !shape!.firstpoint.z Populate field toZ, using lastpoint.z Join 3d lines back to original, using unique id, select ones where fromZ < toZ Use flip edit TOOL to flip selected. It works for ...


4

No. You need a Mapbox Commercial Satellite licence. https://www.mapbox.com/tos/#[YmtIyw] You may trace Mapbox-hosted imagery in order to produce derivative vector datasets for non-commercial purposes, and for OpenStreetMap. If you wish to produce derivative vector datasets from imagery for commercial purposes, you must buy a Mapbox Commercial Satellite ...


3

You can also use the plugin 'Rectangles Ovals Digitizing' for creating rectangles, circles and ovals. Side note: Just read that the new geometry engine of the coming QGIS 2.10 supports curved geometry types. I am not sure how this would apply for circles.


2

The easiest way would be the following: enable snappig on the line layer that you are using to digitize digitize the line, but finish your sketch before you close it digitize another line, start digitizing at the end of the previously digitized line (using snapping), finish the line at the start of the previously finished line (using snapping) now select ...


2

Steven already shared a very good walk-through! I just want to add that you could also use the QGIS LecoS plugin (requires active numpy/scipy installation within your QGIS path) for this purpose. Especially for raster basic cleaning and edge extraction purposes. LecoS has a so-called landscape modifier since some time, which applies scipy's erosion ...


2

I'm not sure how well this will work without trying on your specific raster, but a few pointers. I assume from your image you used Threshold in GIMP to give you a binary raster (inside field/outside field) Removing noise You can use GDAL Sieve to remove the 'salt and pepper' noise - those little holes within the fields. You can do this from QGIS (Raster ...


2

Not sure what version of QGIS you are using. I have 2.8.2-Wien. This has advanced digitising tools that allow creation of circles by selection of two points, selection of three points, selection of centre and input radius and selection of a centre and a point. Just ensure that you have the CADDigitize and CadTools plugins loaded to access some good ...


2

Yes, you can definitely use USGS National map ortho-imagery to extract features, using heads-up digitizing methods (HUD.) The trick here is to work within a projected environment using UTM or State Plane as a coordinate system to ensure fidelity. Another consideration should be the age of the image. Ensure you are working with the most current image possible ...


2

Generally speaking, for vector geometry (e.g. roads, buildings, polygons, areas of interest) these features are created by outside contractors that specialize in geospatial data production. However, the tech companies like Google/Apple/Microsoft must also QA/QC the massive datasets for inaccuracies. A lot of this can be done programmatically by their ...


2

To change the cursor on the application level type into Python console: from PyQt4.QtCore import * from PyQt4.QtGui import * # action cursor QApplication.instance().setOverrideCursor(Qt.BusyCursor) Or to set a custom bitmap as the cursor (this might be simply a yellow cross): # customized cursor ...


2

You can generate a 1 by 8 grid with bounds set to the bounds of you polygon. Then clip your polygon with the cells of this grid. The product would be eight equally proportioned sections of the original polygon.


2

I haven't tried it, but there is the CalcArea plugin, which apparently "calculates the area of a polygon while it's being created or edited".


2

I don't think there will be you can have non-rectangular shapes kept at a constant size, if you move one corner what decides how the others are moved to adjust the size? I would say just create one feature the right size and copy it around as required but since some will be irregular (not right angles) I suggest setting a label with the area so you can ...


2

You didn't specify it in your question but it looks like you are using QGIS. The "Split selected feature with select line from another layer" tool is from the Digitizing Tools plugin. You may need to download/install from the toolbar menu: Plugins > Manage and Install Plugins Once installed and enabled, it should show up in the toolbar. If not then ...


2

First follow this tutorial to convert raster to vector in QGIS. http://manual.linfiniti.com/en/complete_analysis/raster_to_vector.html Next make selections on the shapefile, based on the attribute values of the countries. Finally export the selection.


2

A free tool that will help you explore what you can do within GIS, is QGIS. It will most likely be a little tricky to digitize and import the information but you can start with loading a basemap (say Openstreetmap) and trace out the boundary of your property. Then, you can try to import some scans of your paper copies and geo-rectify them. This just means ...


2

If you do choose to use a CAD, rather than GIS program for your needs, There are also open-source CAD programs like QCAD.


1

The mmu is based on many things. From the picture you have there it is not possible to tell and it should be done before you digitize a map. Some hints how you can estimate the mmu: what are the requirements? the smallest objects that need to be mapped and if they are for example needed as polygon or just as point what are the technical boundaries? for ...


1

You can certainly change the size of the cross using standard properties. I don't think you can change the colour, though. Settings > Options > Digitizing > Vertex Markers and change the size value. Detlev's suggestion is great, although it does affect the whole app, not just digitizing, so be careful how you design the icon (the cursor hotspot seems to ...


1

I wouldn't say it's a hopeless task. After all, these aren't random points - you know they are going to form a linear feature. I spent about 10 minutes with FME - using a dataset of a trail sorted into a random order - and think the NeighborPairFinder transformer is your friend here. It works because for each point on the trail you find the two nearest ...


1

I have downgraded my qgis to version 2.0.1, now it works. It seems to be a bug in the new version.


1

Orthoimagery from The National Map is technically already digital data. Regardless, you may conduct manual on-screen digitizing with USGS orthoimagery as a base to trace specific entities such as houses and roads. Bear in mind the coordinate system of imagery and the feature class you are doing your tracing with to ensure they match while tracing. Also, ...


1

If you are new to GIS, I would recommend using Google Earth Pro (free to use, as of a couple months ago). You could draw polygons in two different layers (residential and commercial). If Excel is only needed to calculate the area, you could simply calculate the area with Google Earth.


1

A workaround is to digitize a temporary line starting from the final start/end vertex for creating something that you can snap to. Delete the helper line afterwards. For a proper fix make a feature request and hope that new snapping option would be implemented sooner or later. With OpenJUMP that has succeeded ...


1

Ok, there is definitely a bug, but I found a temporary fix for it... While I was editing, I had snapping turned on. I needed this in order to snap to boundaries, measure a setback, and then start drawing my feature. I turned snapping off after my measurement line was completed, and... QGIS didn't crash! So, if anyone else runs into this issue, this worked ...



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