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Last edited information missing when used QGIS - Dxf to Shp

Last edited information missing when used QGIS - Dxf to Shp


I am doing as constructed drawings which require the information to be in a GIS system and more specifically drainage as constructed drawings.

I must have a separate file for Pipes and Pits. First I use Autocad, save as a DXF then use Quantum GIS to convert the DXF to SHP. So the problem is that the last edited piece of information from the autocad file is missing when i convert it. I can go back and change the last edited line, polygon or polyline and the last thing touched will still be missing. Help?

I have looked on the QGIS website but haven't been able to find anything helpful.


To lighten some happy mood, I suggest you to use FME Server. Since FME is a very powerful engine, your conversion should be done without much complexion. Figuratively, numerous format can be selected here. But bear in mind that the files should be organized. Otherwise, it would means nothing.

Click here: http://fmeserver.com/userweb/sharper/Portal/EasyTranslator/index.html

The conversion process should works.


QGIS to ArcMap file delivery via geopackage

When I’m saving a new layer made in QGIS (v 3.14), it gives me only an option of saving it as .gpkg file. I sent these to a person using ArcMap for further work and he’s insisting that I send him all (.shp, .dbf, .shx, .prj, .sbn, .sbx). I have used ArcMap before, but within last year I have access only to QGIS.

Is it possible that ArcMap cannot open .gpkg file or there is something else that is the problem?

4 Answers

If you have the GDAL/OGR command line tools installed you can convert a geopackage to a folder of shapefiles (and .dbf files for non-spatial tables) in one line. I'm not sure how to get these installed in Windows/Mac (am using Linux) but it is possible.

I have a geopackage with two layers:

I get a new folder called "shapes" with:

which is one non-spatial layer ( inhours.dbf ) and localauth shapefile set. If there were more layers they would appear here.

I could now zip this folder up to send to someone who really really really can't deal with a geopackage.

Answered 2 months ago by Spacedman with 4 upvotes

I guess they need the files in shapefile format instead of geopackage. Whatever is the file you have to exchange with them you could just export it as shapefile from QGIS. You can do so by right clicking on the file in QGIS, clicking export objects as. the selecting ESRI shapefile on format and then saving it within the folder directory you want. Aditionally you could create a zip file with all the files that you just produced to make file exchanges easier.

Answered 2 months ago by pomegranate with 1 upvote

Shapefile has so many limitations, it's hard to imagine that this would be the preferred exchange format (I'd prefer UTF-8 CSV with Well-Known Text geometry over shapefile). In any case, the .sbn / .sbx components are not part of the shapefile specification, and therefore should not be expected.

It seems the limitation is on the user's part more than on the software, though if this person's Desktop release is elderly (<10.4) there could be geopackage compatibility issues.

QGIS should also be able to create file geodatabase (with the Esri, not Open, FGDB library).

You should be able to negotiate an acceptable format with a little flexibility on both sides.

Answered 2 months ago by Vince with 5 upvotes

ArcMap should be able to open a GPKG, but you may need to follow these steps (I don't believe you can drag and drop)

Alternatively, you can export to ESRI SHP direct from QGIS, although bear in mind this has limitations on field name length (processing tools default to GPKG, but right click on a layer -> Export -> Save As/Save Features As and you should have many more formats)


The Browser Panel¶

QGIS Browser is one of the main panels of QGIS that lets you quickly and easily add your data to projects. It helps you navigate in your filesystem and manage geodata, regardless the type of layer (raster, vector, table), or the datasource format (plain or compressed files, database, web services).

To add a layer into a project:

  1. right-click on QGIS toolbar and check Browser Panel to activate it or select it from the menu View ‣ Panels (or Settings ‣ Panels)
  2. a browser tree with your filesystem, databases and web services is displayed
  3. find the layer in the list
  4. right-click on its name and select Add selected layer(s). Your layer is now added to the Layers Panel and can be viewed in the map canvas.

You can also add a layer or open a QGIS project directly from the Browser panel by double-clicking its name or by drag-and-drop into the map canvas.

Once a file is loaded, you can zoom around it using the map navigation tools. To change the style of a layer, open the Layer Properties dialog by double clicking on the layer name or by right-clicking on the name in the legend and choosing Properties from the context menu. See section Style Properties for more information on setting symbology of vector layers.

At the top of the Browser panel, you find some icons that help you to:

    Add Selected Layers : you can also add data into the map canvas by selecting Add selected layer(s) from the layer’s context menu Refresh the browser tree Filter Browser to search for specific data. Enter a search word or wildcard and the browser will filter the tree to only show paths to matching DB tables, filenames or folders – other data or folders won’t be displayed. See the Browser Panel(2) example on the figure_browser_panels. The comparison can be case-sensitive or not. It can also be set to:
    • normal: return any item containing the search text
    • using wildcard(s): fine tune the search using ? and/or * characters to specify the position of the search text
    • using a regular expression.

    Right-click an item in the browser tree helps you to:

    • in case of file or table, display its metadata or open it in your project. Tables can even be renamed, deleted or truncated
    • in case of folder, bookmark it into your favourites, hide it from the browser tree. Hidden folders can be managed from the Settings ‣ Options ‣ Data Sources tab
    • create connection to databases or web servers
    • refresh, rename or delete schema.

    You can also import files into databases or copy tables from one schema/database to another one with a simple drag-and-drop. There is a second browser panel available to avoid long scrolling while dragging. Just select the file and drag-and-drop from one panel to the other.

    QGIS Browser panels side-by-side

    Add layers to QGIS by simple drag-and-drop from your OS file browser

    You can also add file(s) to the project by drag-and-dropping them from your operating system file browser to the Layers Panel or the map canvas.


    GIS Interview Question – Frequently Asked Question GIS

    Que. What is GIS?
    Ans. GIS is a blend of S/W and H/W used to collect, manipulate analyst and produce geographical data

    Que. What is the difference between geo-coding and geo-referencing?
    Ans. Geo-coding is when you associate a place name or an address with map coordinates. Geo-referencing is the process of associating plain digital images taken from a satellite or a plane with map coordinates so that they can be overlaid on street maps.

    Que. Name the two data structures that have the capacity to hold spatial data.
    Ans. The two data structures that can hold spatial data include raster and vector.

    Que. Differentiate between GIS commands and tools?
    Ans. Commands do not require interaction with the map, they just rely on surface. Tools on the other hand require interaction with the map canvas.

    Que. Name applications of the Arc GIS desktop.
    Ans. Arc Map, Arc catalog and Arc toolbox.

    Que. Define remote sensing?
    Ans. Remote sensing refers to detection and classification of objects on or in earth without physical contact, generally attained through aerial sensors.

    Que. What is the role of GPS in GIS?
    Ans. Competent decisions can only be rendered by reliable data and though GIS is an amazing data management tool, using it with GPS helps in validating the data analysis and results.

    Que. What is a globe?
    Ans. A sphere shaped model of the Earth

    Que. What are the 7 large land massses found on a globe called?
    Ans. Continents

    Que. Name the 7 continents.
    Ans. Asia, Africa, Europe, North America, South America, Antarctica, and Australia.

    Que. Latitude and Longitude are measured in ____ .
    Ans. Degrees

    Que. What does the scale on a map shows?
    Ans. Where you are,How the size of the map relates to the size of a real place and direction as North,east,south,west.

    Que. What does the legend or map key tell?
    Ans. Direction, What the symbols on the map mean and The distance between the equator and a point north or south on the earth’s surface

    Que. What is GPS ?
    Ans. Global Positioning System(GPS) is a space based satellite navigation system that provides location and time information in all the weather conditions, anywhere on or near the earth.

    Que. List the satellite navigation systems ?
    Ans. The navigation systems are as follows:

    1. GLONASS(Globalnaya navigatsionnaya sputnikovaya sistema) : Russia’s global navigation system.
    2. IRNSS ( Indian Regional Navigational Satellite System), COMPASS : People’s republic of china’s global system.

    Que. Explain briefly the working principle of GPS ?
    Ans. A Global Positioning System’s receiver calculates its position by precisely timing the signals sent by Global Positioning System satellite high above the earth. These distances and satellite location are used to compute the location of the receiver using the Navigation Equations. Although 4 satellites are required for normal operation, fewer apply in special cases.

    Que. Explain the structure of GPS ?
    Ans. The structure of GPS have three main segments. These are as follows: Page segment, Control segment and User segment

    Que. Explain the space segment of GPS ?
    Ans. Space segment is composed of 24 to 32 satellites in medium Earth orbit and also includes the payload adapter to the boosters required to launch them into orbit.

    Que. Explain the control segment of GPS ?
    Ans. Control segment is composed of a master control station , an alternate master control station, and a host of dedicated and shared ground antennas and monitor stations.

    Que. Explain the user segment of GPS?
    Ans. User segment is composed of thousands of U.S and allied military users of the secure GPS Precise positioning service and millions of civil and scientific users of the standard positioning service.

    Que. What Is Gps Rollover?
    Ans. This document contains information about GPS Week 1024 Rollover.

    Que. What Is The Status Of Selective Availability (sa)?
    Ans. Effective as of Midnight 01 May 2000, Selective Availability has been set to zero

    Que. Explain Portable Gps?
    Ans. Although any small global positioning system could be referred to as a portable GPS, the term generally refers to those units which give driving directions and are meant to be mounted in cars. Others, used for outdoor activities, are generally referred to as handheld GPS units. Still, there could be some times when the terms are confused and a portable GPS and handheld GPS are synonymous.

    Que. What’s The Status Of The Gps?
    Ans. The Global Positioning System reached full Operational Capability (FOC) on July 17, 1995

    Que. What is a project (.mxd) file?
    Ans. You can think of a project file as a database management tool. GIS users often must work on the same files for long periods of time, and the .mxd file is the management file that remembers which files you use, where they are located, the projection the file is stored in, the colors you have set, etc.

    Que. What is a shapefile?
    Ans. Shapefiles are computer files that produce images for users in a GIS environment. There are three basic types of shapefiles: line poin and polygon.

    Que. How do I prepare spatial data for use with ArcGIS?
    Ans. If you have data with spatial locators (e.g., census FIPS codes, zip codes, street addresses, etc.), you can link your data to shapefiles within a GIS environment. Furthermore, you can join tables in a GIS project.

    Que. What are ArcMap, ArcCatalog and ArcToolbox?
    Ans. ArcMap is the application in ArcGIS that you use to create, visualize, and manipulate maps, whereas ArcCatalog is the application in ArcGIS that you use for browsing and organizing data files. ArcToolbox is the application in ArcGIS that contains data management and conversion tools and wizards (e.g., projection tools).

    Que. What are some of the functions of the Spatial Analyst extension?
    Ans. The Spatial Analyst extension can help you find slopes and directions, least cost paths, and best locations for a new facility based on multiple criteria. This is useful for analyzing raster data as well as feature data.

    Que. What are some of the functions of the Geostatistical Analyst extension?
    Ans. The Geostatistical Analyst extension can help you with the production of statistical surfaces for exploratory spatial data analysis, structural analysis (calculating properties of neighboring areas), and surface prediction and results analysis.

    Que. Is there any way to change or expand existing ArcGIS functionality?
    Ans. ESRI makes a number of scripts and other downloads available for users. Scripts work with the existing software to extend functionality or to automate common tasks. The scripts on ESRI’s site come from both ESRI itself and from other ArcGIS users you can even upload your own scripts for other people to download.

    Que. How do you edit a project (.mxd) file? Why do you need to edit a project file?
    Ans. Once you open your project file, editing is simple. The last saved version of your files will appear on your computer screen, and you can manipulate the existing settings to update the file. (Always remember to save it!) Project files must be edited in order for changes to be reflected in your work. You often work on GIS projects over long periods of time, and as you work, new data, shapefiles, etc. can be added to keep your project current.

    Que. What is the MSD file and can I edit it?
    Ans. The map service definition (MSD) file is a new file used by the fast map service drawing engine introduced at ArcGIS Server 9.3.1. The MSD file always starts with an MXD map document. You use the Map Service Publishing Toolbar to analyze your MXD in ArcMap. Once you’ve addressed issues returned by the analysis, you use the same toolbar to either publish the service or save the MSD file.

    Que. How does GPS device work?
    Ans. The orbits are arranged so that at any time, anywhere on Earth, there are at least four satellites “visible” in the sky. A GPS receiver’s job is to locate four or more of these satellites, figure out the distance to each, and use this information to deduce its own location.

    Que. What is Selective Availability (SA)?
    Ans. SA was a technique implemented by the DOD to intentionally degrade a user’s navigation solution. The single largest source of error for SPS users was SA. The net result of SA was about a five-fold increase in positioning error. DOD achieved signal degradation by altering (also known as dithering) the satellite clock. Another means designed by DOD to degrade GPS performance was to broadcast less accurate ephemeris parameters.

    Que. Why was SA Necessary?
    Ans. SA was used to protect the security interests of the U.S. and its allies by globally denying the full accuracy of the civil system to potential adversaries.

    Que. Will SA ever be turned back on?
    Ans. It is not the intent of the U.S. to ever use SA again. To ensure that potential adversaries to do not use GPS, the military is dedicated to the development and deployment of regional denial capabilities in lieu of global degradation through SA.

    Que. What kind of orbits are the GPS satellites in?
    Ans. The GPS satellites operate in circular 10,900nm (20,200km) 12-hour orbits at an inclination of 55 degrees. They are not in geo-stationary orbit.
    How vulnerable are GPS satellites to jamming and interference?
    GPS satellite signals, like any other navigation signals, are subject to some form of interference. The FAA is actively working with the U.S. Department of Defense and other U.S. Government Agencies to detect and mitigate these effects and make sure that the GPS and any related augmentation systems are available for safe aviation operations. As with all navigation aids, interference, whether intentional or unintentional, is always a concern.

    Que. Is the basic GPS signal sufficient to meet all the needs of civil aviation?
    Ans. This is not a simple yes/no answer. The answer is that it depends on the service requirements of each user or aviation authority. For many countries, GPS supplies a better capability than the existing ground-based systems or lack thereof. Yet for other countries with large infrastructures, the GPS signal does not meet the accuracy, integrity, availability, and continuity requirements critical to safety of flight. Enhancements to the Global Positioning System (GPS) such as the Wide Area Augmentation System (WAAS) and Ground Based Augmentation System (GBAS) provide the necessary corrections for meeting safety-of-life flight requirements.

    Que. What is Differential GPS (DGPS)?
    Ans. In the basic form of DGPS, the position of a reference receiver at a monitoring or reference station is surveyed in, that is, its position is known accurately. The user receiver should be no more than about 300 miles away from the reference receiver which makes pseudorange measurements, just as any user receiver would. However, because the reference receiver knows its position accurately, it can determine “biases” in its pseudorange measurements. For each satellite in view of the reference receiver, these biases are computed by differencing the pseudorange measurement and the satellite-to-reference receiver geometric range. These biases incurred in the pseudorange measurement process include errors arising from ionospheric delay, tropospheric delay, and satellite clock offset from GPS time. For real-time applications, the reference station transmits these biases, called differential corrections, to all users in the coverage area of the reference station. Users incorporate these corrections to improve the accuracy of their position solution.

    Que. Will the GPS tracking system make the fleet management easier?
    Ans. Fleet management involves managing vehicles and personnel available. It also constitutes route planning, route optimization, personnel management, asset tracking, vehicle maintenance, report generation, fuel management, etc.

    Que. What are the gains of implementing student GPS tracking system?
    Ans. You need to be clear about the potential gains of installing a vehicle tracker in the school buses before you start out on a GPS tracking system. Is it truly worth the cost and effort? Does it provide what it promises to offer? You should also consider getting a detailed demo run so that you will be able to understand the functioning of the system.

    Que. Do you need a cost effective solution for vehicle fleet management?
    Ans. The budget for each school to implement an effective solution would definitely vary. For this reason, you should consider the number of vehicles, data base needed (e.g. up to street level), additional facilities required, such SMS or PUSH notification facilities, etc. It should be decided whether all the features offered in a system is actually useful for you. There are advanced systems which even offer guided voice directions to make school bus trips less cumbersome for bus drivers and attendants.

    Que. What is the potential for a gap in GPS service?
    Ans. The Air Force is confident GPS will continue to meet existing service commitments. Several years ago, the Air Force recognized the potential for an availability gap and took action to institutionalize procedures and processes to mitigate the potential gap or minimize any impact. Air Force Space Command developed key processes within the operational community as well as the acquisition community to extend the life of on-orbit assets and to ensure capability is delivered in a timely manner. Users can employ GPS with confidence today and continue to do so in the future. As identified by the General Accounting Office (GAO) in testimony to Congress, “There have been times before where people have worried about gaps and the Air Force has managed them quite successfully.”

    Que. Is GPS under U.S. military control?
    Ans. Though acquired and operated by the Department of Defense, GPS is a multi-use system owned by the United States Government and paid for by the U.S. taxpayer. The outstanding performance of GPS over decades has earned the confidence of millions of civil and military users worldwide. The management structure and modernization efforts directed by U.S. policy continue this support for multi-user applications. Any misperceptions will be overcome as they have in the past, by a demonstrated record of service and performance to all users.

    Que. What are the benefits of GPS tracking?
    Ans. GPS tracking tells you which employees are on the clock and where they’re located. You’ll be able to see who is closest to a customer when scheduling a new job on the fly, more effectively manage employees at various locations, identify inefficiencies in workloads and routes, and build trust by adding accountability safeguards that benefit everyone.

    Que. How accurate is the GPS location data from the GPS device?
    Ans. Different GPS devices offer differing levels of accuracy so always ask the question. AVS GPS devices have a high level of GPS accuracy of between 5 and 10 metres or better with clear skies.

    Que. What is a GPS locator?
    Ans. A GPS locator does not record regular position updates, it will only log its position on command. Simply send a TXT to the tracker and it will TXT back its’ location. Some GPS locators will send GPS co-ordinates (Latitude and Longitude) which can then be entered into Google to bring up a map.

    Que. What are the limitations of GPS tracking?
    Ans. GPS tracking is not invincible and no GPS hardware will be able to guarantee position logs 100% of the time. GPS devices rely on being able to communicate with the satellites in space and so in highly built up areas or underground carparks reception can be blocked.

    Que. What is GPS tracking?
    Ans. GPS tracking is a way of determining the location of a vehicle, person or other asset. A GPS device is attached to, or installed into, the asset you wish to track. The device then uses the Global Positioning System to record the position of the asset at regular intervals.

    Que. what is trilateration?
    Ans. A GPS receiver uses trilateration (a more complex version of triangulation) to determine its position on the surface of the earth by timing signals from three satellites in the Global Positioning System.

    Que. What is the difference between triangulation and Trilateration?
    Ans. As GPS satellites broadcast their location and time, trilateration measure distances to pinpoint their exact position on Earth. While triangulation is associated with surveying, no angles are actually involved in GPS positioning. Surveyors usetriangulation to measure distant points – not GPS receivers.

    I hope this Question answer might have helped you in understanding Geographical information system and in clearing the Basics interview question of Geographical information system. Let us know if you have any other list of questions answer available in Geographical information system by commenting below in the space provided.


    QGIS Vector Geometry Vanished

    I’ve been working on a project, in QGIS 3.16 Hannover (we started the project a while ago, in the Bonn version, but upgraded during the duration of project). Upon project completion we’ve been asked to hand over the shape files also, not just the layout pdfs.

    As it turned out, the last version of the shp is missing geometry of most attributes. The attribute table contains up-to-date state, but most of features now have no geometry, i.e. they exist as entries in the attribute table, but have null geometry.

    Does anybody have a solution? Is it possible that this situation arose, because me and my colleague worked on the same project, often simultaneously? I.e. could it have happened because we inadvertently wrote over same shapefiles at the same time?

    Also, what is the latest on archiving QGIS projects? Is there an automatic function available?

    I guess I’ll live with the loss of data in this case, probably it’ll take me a day to recover (that is draw missing geometries by hand).


    Git models the history of a collection of files and folders within some top-level directory as a series of snapshots. In Git terminology, a file is called a “blob”, and it’s just a bunch of bytes. A directory is called a “tree”, and it maps names to blobs or trees (so directories can contain other directories). A snapshot is the top-level tree that is being tracked. For example, we might have a tree as follows:

    The top-level tree contains two elements, a tree “foo” (that itself contains one element, a blob “bar.txt”), and a blob “baz.txt”.


    Kgjenkins / README.md

    "GIS data" refers to data with a spatial component -- it can be mapped!

    QGIS is one of several popular GIS programs for mapping and spatial analysis. It is free, open-source desktop software that runs on Windows, Mac, and Linux. QGIS is created by developers around the world, supported by municipal and national governments, corporations, user groups, and individual users. Discussions about new features, bug fixes, and future directions happen on e-mail lists and the project's GitHub organization.

    Questions about how to use QGIS are typically asked and answered on GIS StackExchange. If you google for QGIS questions, there is a good chance you'll end up finding the answer already there, so search before asking a new question.

    Vector = points, lines, polygons

    Raster = pixels (images, but also data)

    Data = Geometry + Attributes

    Vector data does not usually contain any information about how to style the display of the data.

    Styles are added in a map project. The same data could be styled in different ways in different maps, or even in the same map!

    The QGIS project file .qgz contains your styles and pointers to the data, but does not include the data itself. I recommend keeping everything within a containing folder (there can be subfolders) that you can zip up or save to a device or the cloud.

    CRS = Coordinate Reference System

    Ideally, CRS details are quietly handled behind the scenes, so we barely even need to think about it.

    But in the real world, you'll eventually run into CRS puzzles, and CRS becomes even more important when doing distance- or area-based analysis.

    • EPSG:4326 = WGS 84 -- "common longitude/latitude"
    • EPSG:4269 = NAD83 -- longitude/latitude, similar to WGS 84, but only defined for North America
    • EPSG:3857 = WGS 84 / Pseudo-Mercator -- also called "Web Mercator", uses false "meters" (only true at equator)
    • EPSG:3452 = NAD83 / Louisiana South (ftUS)
    • EPSG:26915 = NAD83 / UTM zone 15N (meters)

    "Parishes" in Louisiana are what other states call "counties". The parishes.gpkg file was extracted from a 2019 nationwide county boundary shapefile that was downloaded from https://www.census.gov/cgi-bin/geo/shapefiles/

    QGIS was used to select just the Louisiana polygons and export them to a geopackage. GeoPackage is a modern, open geospatial data format that is supported by most GIS software.

    Load the parish boundaries:

    Change the layer style by opening the Layer Styling panel – colorful paintbrush icon at top left of the Layers panel

    • Change the color
    • Click "Simple fill" to change other properties, like stroke color and width

    Get information about a parish:

    View information about all the parishes as a table:

    • Right-click layer in Layers pane > Open Attribute Table
    • Click the "NAME" column header to sort by that column

    The table and map are linked, so select Orleans from the table (by clicking the row number) to see it highlighted on the map. There is a toolbar button to "Deselect features from all layers".

    Add labels by clicking the label tab (yellow "abc") in the styling panel

    • Single Labels, value = NAME
    • 9 tabs of options!
    • 1st tab (text) - font, size, color
    • 2nd tab (formatting) - wrap lines to 12 characters
    • 8th tab (placement) - Horizontal

    To find out what CRS (coordinate reference system) is being used:

    Save "mymap.qgz" to the folder that also contains your data -- for example, within the "QGIS-workshops" folder. That way, you can zip up or move the containing folder around while keeping your map and data intact. The .qgz project file contains your map styles and pointers to your data files, but not the data itself.

    The City of New Orleans has a dataset of road centerlines -- one line per road, regardless of how many lanes it has. This data is in a shapefile format, which is probably the most common geospatial data format found on the Internet, but the shapefile format dates from the early 1990s, which is why there are multiple component files (.shp, .dbf, .shx, .prj, and sometimes others). To add a shapefile to QGIS, we just need to select the .shp file and QGIS will take care of the rest. Shapefiles also have other quirks, mostly notably a 10-character limit for attribute names. Learn more at http://switchfromshapefile.org/

    Explore the data a bit (identify tool, attribute table), and notice the contents of the "ROADCLASS" column. We can use those values to control the layer style.

    • At the top of the layer styling panel, change "Single symbol" to "Categorized"
    • Set Value = "ROADCLASS", then click the "Classify" button towards the bottom of the panel

    Random colors are assigned to each of the values, which is not really what we want. You can shift-click to select all the values, then right-click to change the color for all the values at once.

    • Change all the road colors to black
    • Double-click the "Freeway" symbol to edit it -- change the width to 1.5mm
    • Change the "Major Arterial" width to 0.75mm

    Try turning on labels for the roads and zooming in and out a bit.

    There are many options that can be configured to improve the appearance of the labels, but it can require a lot of work and even manual adjustments to make it look really good, so.

    Basemaps via QuickMapServices

    Basemaps are web-based map images designed by professional cartographers who have already done the hard work of aggregating different data layers and customizing styles and labels to work at different zoom levels. Basemaps are usually global in scope, although there are some that only focus on certain regions. They can be used to add context to your map, or just to help confirm that your data is correctly aligned. The QuickMapServices plugin makes this easy, but we need to install it first.

    • Plugins menu > Manage and Install Plugins.
    • Scroll down, or search all plugins for "quickmap" (you don’t need to type the whole name)
    • Select the QuickMapServices plugin
    • Click the "Install plugin" button (it installs in seconds)
    • Click "Close"

    When you first install QuickMapServices, you'll want to get the full set of basemap definitions.

    To add the Google Hybrid basemap, which combines aerial photos with placename labels:

    • Web menu > QuickMapServices > Google > Google Hybrid
    • Turn off your roads and parishes in order to see the basemap

    Most basemaps are in a different projection (CRS) called Pseudo- or Web-Mercator, EPSG:3857. QGIS is reprojecting it to match the CRS of our parishes, which can cause some pixelation, making the labels hard to read. If you zoom out, you'll notice that the US looks stretched out.

    To avoid the pixelization and the stretched shapes, we can set our map to use the basemap CRS:

    • Right-click the Google layer > Set CRS > Set Project CRS from Layer
    • Right-click the Google layer > Zoom to Native Resolution (100%)

    Turn the roads layer back on, and explore how well it aligns with the imagery.

    Turn on the parish layer, and adjust the style to work better with the basemap:

    • Click "Simple fill", then set fill style = No Brush
    • Set the stroke color to orange
    • Switch to the label tab and set the label color to orange
    • 3rd tab (buffer) - Draw text buffer, 1.5mm black

    As we add more data, it will help to use a plainer basemap:

    • Web menu > QuickMapServices > Stamen > Stamen Toner Lite
    • Uncheck the Google Hybrid layer to hide it
    • Adjust the parish style as needed (white buffer, for example)

    The Stamen Toner Lite layer is very light, so we can add our own roads on top if we want to emphasize the New Orleans road network.

    • In the roads style panel, adjust Layer Rendering > Opacity to control the visual weight of the roads

    As an example of point data, we will look at a dataset of COVID-19 Testing Sites. The Louisiana Department of Health website lists the public testing sites available in each parish. However, as is often the case with infomation on the web, this list is not readily accessible as data that can be used to make a map. The information is displayed in a dynamic widget where the user must first click on a small map, and then there is no way to directly download the data for the 25 testing sites in Orleans parish. And even if it could be downloaded, it only contains a street address, which would have to be geocoded -- QGIS has tools for this -- in order to get the longitude/latitude coordinates necessary to display the sites as points on a map.

    Fortunately, a team of volunteers from the GISCorps, a program organized the URISA (Urban and Regional Information Systems Association), has collected and aggregated COVID-19 data from across the country, and offers a nationwide dataset of testing sites.

    • Look in the "covid-test-sites" folder, and drag the .shp file onto QGIS
    • Explore the data a bit (identify tool, attribute table)
    • Adjust the display style as you see fit -- maybe try "Categorized" by "status" or "drive_thro"

    Notice that this dataset covers the whole United States, including Alaska and Pacific island territories. We can use this dataset to extract just the points for the area around New Orleans, and save them to a new file.

    • Zoom back in to New Orleans so that you can see all of the city with plenty of margin.
    • Click the "Select Features by area or single click" tool in the toolbar (the 1st of three yellowing icons in a row)
    • Click the "Testing_Locations" layer name, then drag a rectangle around the points surrounding New Orleans (better to select too many than not enough)

    Those points should appear yellow to show that they have been selected.

    • Right-click the "Testing_Locations" layer name > Export > Save Selected Features As.
    • Format = GeoPackage
    • Click the ". " to set the file location and name -- call it "covidsites.gpkg"
    • The layer name will automatically copy the filename (before the .gpkg extension) -- best practice is to only use letters, numbers, and underscores, although QGIS is fairly forgiving, unlike some other GIS software.
    • Leave the CRS as is (EPSG:4326 - WGS 84)
    • Click "OK"

    The exported file will automatically be added to the map. You may now remove the original testing sites layer:

    Inverted Polygons to mask surrounding areas

    One last trick, to set the focus of our map on the City of New Orleans, will be to mask the areas outside the single Orleans parish. The "inverted polygon" option will apply a style to the outside (rather than the inside) of a polygon.

    • Right-click the parishes layer > Filter.
    • Enter the following expression: "NAME" = 'Orleans'
    • In the styling panel, change "Single symbol" to "Inverted polygons"
    • Click "Simple fill" and set the fill style to "Solid"
    • Set the Fill color and Stroke color to black
    • Click "Fill" to get to the option for setting the feature opacity, setting it around 65%

    Exporting your map to an image file

    To export the current map view to an image file:

    • Project menu > Import/Export > Export Map to Image.
    • Update the extent or leave as is
    • Increase the resolution (try 300dpi)
    • Save as a .png file

    Exporting your map to a PDF file

    Exporting to PDF is useful if you are going to print your map, or if you want to do further work in a program like Inkscape or Adobe Illustrator. The PDF will keep separate layers for each data layer. Vector layers will remain vectors, and raster layers will remain raster.

    • Project menu > Import/Export > Export Map to PDF.
    • Check the settings, especially the resolution if your map includes raster layers, including basemaps

    Exporting data layers to a DXF file (for CAD software)

    Architects often want to export GIS layers for use in a CAD program like Rhino or AutoCAD. Since DXF is a vector format, only vector layers can be exported -- sorry, no basemaps! When exporting to CAD, be sure to set an appropriate CRS for the exported data, which means a CRS based on meters or feet -- not degrees longitude/latitude.

    • Project menu > Import/Export > Export Project to DXF.
    • Click the ". " button to specify where to save the .dxf file
    • Be sure to select an appropriate CRS! QGIS will reproject all your layers to the chosen CRS.

    Coming next. on QGIS Workshop Day 2

    • elevation data - pseudocolor, hillshades, and contours
    • levees
    • imagery webservices
    • georeferencing scanned maps
    • demographic data
    • transit routes
    • oil and gas wells
    • current covid-19 cases
    • other data sources

    Parish boundaries were extracted from US Census shapefiles, which contain many other types of boundaries as well.

    The City of New Orleans has an Open Data Portal with many geospatial layers, including:

    There are even more datasets in the portal, so be sure to search there for more.

    Cemeteries in New Orleans have been mapped pretty well in OpenStreetMap (OSM), a collaborative map of the world that is the most complete map of streets in the world, with better coverage than even Google and Bing. OSM contains much more than streets, and there are many ways to download OSM data, such as this link to an Overpass query:

    Oil Refinery locations are available as part of a collection of Homeland Infrastructure Foundation-Level Data:


    5 Free GIS Mapping Software

    Our goal is to present an overview of Free GIS Mapping Software projects “Basically Desktop GIS” that develop and facilitate free and open source GIS adoption in business, research and teaching. Below is the list of 5 Free and open source Mapping software that is in focus in recent years.

    Many software projects that focus on the development of free Geographic Information Systems (GIS) Mapping software have been initiated in recent years. In particular, the Quantum GIS project, the PostGIS project, and the OpenLayers project have been able to attract users and developers, which has subsequently influenced software functionality and support and as a consequence raised their attractiveness to new users of free software.

    Why Use Open Source GIS Software?

    An open source software means, user can access the software freely and can also modify the source code of that software based on the need. Open Source Projects are typically developed by a community of volunteer programmers. The last few years have seen dramatic development in GIS technology. These Open source GIS application are based on different programming languages. Three main groups of Open Source GIS in terms of programming languages are: C language, Java language, and .NET language (Microsoft). Therefore, the GIS community would get much benefit from the availability of Open Source GIS Application. This community would make a positive impact by allowing the user access to a wider range of tools.

    QGIS – Quantum GIS

    Launched in 2002, QGIS is a free and open source Geographic Information System, licensed under the GNU General Public License. QGIS software includes Key features such as importing of data from multiple sources, digitizing, on the fly reprojection of data, editing of files, data analysis, database connectivity, geoprocessing and raster data processing. Multiple formats of raster images are supported, and QGIS can also georeference images. The extremely capable print layout functionality is intuitive and straightforward for new users to create professional looking maps.

    QGIS considered being the best free geographic information system (GIS) Mapping software, allowing users to analyze and edit spatial data, additionally to composing and exporting graphical maps. QGIS supports both raster layers and vector layers, vector data is stored as either point, line or polygon features. QGIS supports shapefiles, coverages, personal geodatabases, dxf, MapInfo, PostGIS, and different formats. web services, including Web Map Service and Web Feature Service, are supported to permit the use of data from external sources.

    gVSIG Desktop is a Geographical Information System, i.e, a computer application aimed to represent, edit, analyze and manage information from the point of view of spatial relations. The gvSIG license is GNU/GPL v.3 which gives the user the rights to free use, study, improvement and distribution. The gvSIG first version was released in 2004. Developed under the values of collaboration and sharing knowledge, gvSIG has evolved very quickly and in a few years, it has become one of the most used applications to manage the geographical information. gvSIG is known for having a user-friendly interface, being able to access the most common formats, both vector and raster ones. It’s Being developed using Java , and being available for Linux , Windows and Mac OS X platforms.

    Geographic Resources Analysis Support System (GRASS) is a GIS software application that was developed by the US Government. It is an Open Source software providing powerful raster, vector and geospatial processing capabilities in a single integrated software suite. It has over 350 modules for spatial analysis of geospatial information, and the processing of satellite and aerial imagery. Due to Open source GRASS is presently utilized in academic and business settings around the world, as well as by several governmental agencies. GRASS is an official project of the Open Source Geospatial Foundation. It runs on multiple operating systems, including OS X , Windows and Linux .

    MapWindow is more than just a GIS data viewer. This implies that advanced users or developers can write plug-ins to include additional useful functionality (models, special viewers, hot-link handlers, data editors and so on) and pass these along to any number of the user’s clients and end users. It has been adopted by the United States Environmental Protection Agency as the primary GIS platform for its BASINS (Better Assessment Science Integrating Point and Nonpoint Sources) watershed analysis and modelling software.

    OpenJUMP is an open source Geographic Information System (GIS) package written in Java programming language, so you can run it on any working operating system that supports this programming language. It serves multiple purposes, from opening and viewing GIS data to editing geometric data and attributes. It can read and write shapefiles, straightforward GML files and in addition a few other other vector formats via plugins or modules. It can also read from several spatial databases and write to PostGIS database. It supports for images and for WFS and WMS web-services. It is developed and maintained by a group of volunteers, Formerly known as JUMP GIS.


    KML to DXF Convert

    Are you looking for converting your KML data file into DXF format for using it in your GIS project or it into CAD system? Have you extracted and downloaded kml file from Google Earth or Google map and want to render it with your geo library which support dxf format? If so, here is an article to convert KML to DXF format using this amazing online conversion tool.

    You can use any of the tools to convert your kml data file to any other format available in market, but If you don’t want to spend so much time just on conversions and want an easy way for conversions. Here is an amazing tool for converting your data files within a minute, i.e. IGIS Map Converter.

    IGIS Map Converter

    IGIS Map converter is an incredible tool for data file conversions. It will translate an AutoCAD file (in DXF format) to a shapefile or KML format. It can also convert from KML format to shapefile, or KML to DXF, or Shapefile to DXF. It Convert GIS / CAD files online without using complex and Enterprise Software like ArcGIS, QGIS, AutoCAD etc. IGIS Map converter is much easier to use then any other conversion software or tool.

    How to convert KML to DXF format

    • Now just drag or upload your KML file from your system or access the file from Google Drive or Dropbox.

    • Once the file is upload is completed, select the output file format that we want to convert it into i.e. DXF.

    • Now for setting up the conversion process we have to set the CRS (Coordinate reference system), if we want to or otherwise default commonly used CRS is already selected. We can select or change the CRS according to our needs from the change CRS button.

    • Now click the Convert file button to convert the data file formats.
    • And you see a new dashboard with two partition, One for downloading or deleting your new DXF file format. and other one which shows the file content area i.e bounding box area of kml file.

    • You can Download your converted file here or delete it whatever you want, When you scroll down you can see My drive section where all of your converted data files stored. You can publish or delete them according to your requirement.

    • You can also publish your DXF file as map to see the content in the file or to check the conversion.
    • You can also search locations, add new datasets, edit layers and style the map according to your choice and requirements.

    • IGIS Map Converter Tool provides many benefits other then just conversion of data. This tool provides us to generate this published map in PDF or as image format.

    Info GIS Map supports most of the commonly used GIS or AutoCAD files like Shapefile SHP, KML, KMZ, CSV, TopoJSON, GeoJSON, GML, DXF, GeoTIFF, NetCDF, GRIB, HDF5, OSM, PBF, and many more raster and vector files, along with that it support more than 4000 Coordinate Reference System.

    IGIS Map Converter is a online tool for converting GIS data files from one format to another. which helps you in easy data conversion and beautiful and incredible map creation in no time. IGIS Map converter online tool is recommended for better and easy conversions. If you want you can also use ogr2ogr offline conversion tool for convert KML to DXF format.

    If you face any problem during implementing this tutorial, please let us know. Feel free to comment in given comment box.


    Features¶

    QGIS offers many common GIS functionalities provided by core features and plugins. As a short summary they are presented in six categories to gain a first insight.

    View data¶

    You can view and overlay vector and raster data in different formats and projections without conversion to an internal or common format. Supported formats include:

    • Spatially-enabled tables using PostGIS and SpatiaLite, vector formats supported by the installed OGR library, including ESRI shapefiles, MapInfo, SDTS, GML and many more.
    • Raster and imagery formats supported by the installed GDAL (Geospatial Data Abstraction Library) library, such as GeoTiff, Erdas Img., ArcInfo Ascii Grid, JPEG, PNG and many more.
    • SpatiaLite databases (see Section `label_spatialite`_ )
    • GRASS raster and vector data from GRASS databases (location/mapset), see Section `sec_grass`_ .
    • Online spatial data served as OGC-compliant Web Map Service (WMS) or Web Feature Service (WFS), see Section `working_with_ogc`_ .
    • OpenStreetMap data (see Section `plugins_osm`_ ).

    Explore data and compose maps¶

    You can compose maps and interactively explore spatial data with a friendly GUI. The many helpful tools available in the GUI include:

    • on the fly projection
    • map composer
    • overview panel
    • spatial bookmarks
    • identify/select features
    • edit/view/search attributes
    • feature labeling
    • change vector and raster symbology
    • add a graticule layer - now via fTools plugin
    • decorate your map with a north arrow scale bar and copyright label
    • save and restore projects

    Create, edit, manage and export data¶

    You can create, edit, manage and export vector maps in several formats. Raster data have to be imported into GRASS to be able to edit and export them into other formats. QGIS offers the following:

    • Digitizing tools for OGR supported formats and GRASS vector layer.
    • Create and edit shapefiles and GRASS vector layers.
    • Geocode images with the Georeferencer plugin.
    • GPS tools to import and export GPX format, and convert other GPS formats to GPX or down/upload directly to a GPS unit (on Linux, usb: has been addedto list of GPS devices).
    • Visualize and edit OpenStreetMap data.
    • Create PostGIS layers from shapefiles with the SPIT plugin.
    • Improved handling of PostGIS tables.
    • Manage vector attribute tables with the new attribute table (see Section `sec_attribute_table`_ ) or Table Manager plugin.
    • Save screenshots as georeferenced images.

    Analyse data¶

    You can perform spatial data analysis on PostgreSQL/PostGIS and other OGR supported formats using the fTools Python plugin. QGIS currently offers vector analysis, sampling, geoprocessing, geometry and database management tools. You can also use the integrated GRASS tools, which include the complete GRASS functionality of more than 400 modules (See Section `sec_grass`_ ).

    Publish maps on the Internet¶

    QGIS can be used to export data to a mapfile and to publish them on the Internet using a webserver with UMN MapServer installed. QGIS can also be used as a WMS or WFS client, and as WMS server.

    Extend QGIS functionality through plugins¶

    QGIS can be adapted to your special needs with the extensible plugin architecture. QGIS provides libraries that can be used to create plugins. You can even create new applications with C++ or Python!

    Core Plugins¶

    1. Add Delimited Text Layer (Loads and displays delimited text files containing x,y coordinates).
    2. Coordinate Capture (Capture mouse coordinates in different CRS).
    3. Decorations (Copyright Label, North Arrow and Scale bar).
    4. Diagram Overlay (Placing diagrams on vector layer).
    5. Displacement Plugin (Handle point displacement in case points have the same position).
    6. Dxf2Shp Converter (Convert DXF to Shape).
    7. GPS Tools (Loading and importing GPS data).
    8. GRASS (GRASS GIS integration).
    9. GDALTools (Integrate GDAL Tools into QGIS).
    10. Georeferencer GDAL (Adding projection information to raster using GDAL).
    11. Interpolation plugin (interpolate based on vertices of a vector layer).
    12. Mapserver Export (Export QGIS project file to a MapServer map file).
    13. Offline Editing (Allow offline editing and synchronizing with database).
    14. OpenStreetMap plugin (Viewer and editor for openstreetmap data).
    15. Oracle Spatial GeoRaster support.
    16. Plugin Installer (Download and install QGIS python plugins).
    17. Raster terrain analysis (Raster based terrain analysis).
    18. Road graph plugin (Shortest Path network analysis).
    19. SPIT (Import Shapefile to PostgreSQL/PostGIS).
    20. SQL Anywhere Plugin (Store vector layers within a SQL Anywhere database).
    21. Spatial Query Plugin (make spatial queries on vector layers).
    22. WFS Plugin (Add WFS layers to QGIS canvas).
    23. eVIS (Event Visualization Tool).
    24. fTools (Tools for vector data analysis and management).

    External Python Plugins¶

    QGIS offers a growing number of external python plugins that are provided by the community. These plugins reside in the official PyQGIS repository, and can be easily installed using the Python Plugin Installer (See Section `sec_plugins`_ ).

    What’s new in version CURRENT¶

    Please note that this is a release in our ‘cutting edge’ release series. As such it contains new features and extends the programmatic interface over QGIS 1.0.x and QGIS 1.6.0. We recommend that you use this version over previous releases.

    This release includes over 277 bug fixes and many new features and enhancements.