GIS Training book done!

June 9th, 2014

We’ve finished the learning GIS via QGIS  book and it is in the process of publishing.  We’ll let you see the pre-design cover and tell you that it will be available on AMAZON soon!

The authors are Nik Freeman and McCartney Taylor. (Note: the important author goes last)

 

The book is a workbook that evolved from our training courses over 3 years. It will be aimed at the beginner, walk them through important concepts, then give them data and start using QGIS to make a map.  The formula was very successful in training hundreds of Oil and Gas people in how to use basic GIS. And it saved thousands of dollars by showing them how they can use the free QGIS instead of ESRI.

Expected release date June 30, 2014.

gis-book-cover

QGIS Just a few quick tips

August 14th, 2013

Here a few quick tips I wanted to share in QGIS. Under Vector>Analysis Tools there is the basic statistics tool. What it does is fairly simple, but it often gets overlooked.  This will give you data such as mean, median, mode, standard deviation and range. Be careful when choosing the correct column. I noticed that I can choose st_name and it will still try and return results.

Screenshot from 2013-08-14 15:26:54

 

Another is creating labels in Qgis. There are actually two ways to do this. Each way allows you to d different things.  You can download plugins to give more functionality. First and the one I use the most is under layer>labeling

 

Screenshot from 2013-08-14 15:32:05

 

Screenshot from 2013-08-14 15:33:40

This is the layer menu that gives me the most functionality. And it maybe different for others. It gives a sample of the labels being created and provides a lot of advanced features. I tend to use this when I am mass labeling something or I need them to look really good for something such as a presentation.

The other way to create labels is to right click on the layer>Properties> and the labels tab.

Screenshot from 2013-08-14 15:37:40

This I can use for something quick or just a few labels. But even under the advanced tab you lose some of the functions. Such as being able to suppress labeling certain features.

Next under Vector>Geometry Tools> Export/Add Geometry columns. This is simple. It will give you area and perimeter and the options are to either save the results to a new shapefile or add to the current one.

Lastly is editing from the attribute table. This isn’t really editing, but you can delete features. Again this is another simple one, but often overlooked.  In the attribute table at the bottom you have the editing pencil. Once editing is turned on you can now change information in the attribute table and by hitting the red x you can just delete features that way.

Screenshot from 2013-08-14 15:42:32

QGIS Sextante Plug-in

August 14th, 2013

In QGIS there are 100’s of plugins available. One of the best I have used is the SEXTANTE plugin. You can download this by going to Plugins>Fetch Python Plugins and search for SEXTANTE.

Once downloaded it should create it’s own menu called Analysis. I just clicked SEXTANTE toolbox and this is what it looks like.

 

Screenshot from 2013-08-14 15:12:34

SEXTANTE can be literally thought of a as toolbox. It has almost everything you need. In the options you can choose to turn on the listed tools.  Some of the options are modeler, the QGIS tools such as interpolation and DEM analysis are included. Tools for LiDAR database management, creating scripts and the list goes on.

Screenshot from 2013-08-14 15:14:31

 

 

SAGA GIS

August 8th, 2013

 

SAGA GIS is a stand alone program for processing geospatial data. It can be added to Qgis as a plugin under the Sextant tool bar in the options menu. In order for it to work in Qgis you need to have SAGA installed.  SAGA is available for Windows and Linux users only at this time. The code has been released under FOSS or Free and Open Source Software so if you own a Mac and have experience with coding you can create this program for a Mac.

SAGA was started in 2001 by J. Böhner and O. Conrad and the University of Hamburg.  SAGA stands for System for Automated Geoscientific Analysis. If you want to read more about the history and development you can check out the homepage.

 

 

For the remaining screenshots I will be using Ubuntu 13.04

 

 

 

 

 

 

 

When I open SAGA this is what is looks like. Pretty much a blank page with some menu options at the top and a message bar at the bottom.

 

Screenshot from 2013-08-08 10:13:38

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Customization is fairly easy. Under the window you can choose what windows you wants open.

 

Screenshot from 2013-08-08 10:18:38 Screenshot from 2013-08-08 10:17:33

 

In the screenshots here. I have the windows all open within SAGA and the other I moved them outside. They will stay outside but if you move them too close to the main program they will snap back. The windows open are “Workspace” or the tools available. This is confusing because under the menu bar the same information is called modules. Then the file locations. And then a window that houses the most recent tool run.

 

 

 

 

 

The types of files you can load into SAGA are .CSV, .TXT and .shp files. It will also allow you to create projects.

 

It will allow you to bulk upload as many files as you need and once you do they appear in your workspace under the data window. There is not visual of the data in the main window. You can select thumbnail to see it. When clicking on different .shp files the open files window will update.

Screenshot from 2013-08-08 10:30:48 Screenshot from 2013-08-08 10:34:19

 

In this next graphic I did a lot of things. I used a point layer and ran the module Tin Tool>Shapes to Tin. It created a TIN file. Just to be clear it used triangular irregular network. I double clicked to have the image come up in the main window. You can look at the attribute table, change the color all from the top window. Note: The layers are saved using SAGA’s own extension, but there is the option to convert them if needed.

Screenshot from 2013-08-08 10:46:24

 

 

 

 

 

 

 

 

 

 

 

 

 

SAGA is something that could take forever to know %100 percent. At first glance this is a very powerful stand-alone GIS tool. I say stand-alone because it works great by it’s self. You have more tools in the module that anyone one person is ever going to need. Need a few simulations on the effect of human population, lightning analysis,  and point clouds it has you covered. You have the option to add map layers and even create maps for printing. In Qgis by enabling the SAGA plugin you have some of the functionality. I did noticed a few tools missing. SAGA is not for the light user of any GIS system, it has one purpose and that is to analyze data.

 

A few resources/tutorials on using SAGA.

http://www.saga-gis.org/en/about/references.html

http://live.osgeo.org/en/quickstart/saga_quickstart.html

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Solving Issues Downloading Qgis for Ubuntu 13.04

July 17th, 2013

I downloaded Qgis for Ubuntu 13.04 and I encountered a few issues.

First issue I had was that I was not able to download any plugin-ins. Second issue is that I was having is that I was not able to download and use the sextante plugin after solving my initial problem.

Before starting I would do a clean install of Qgis if you have been having problems

sudo apt-get purge qgis

If you having issues downloading plugins:

I found this tutorial online and it is from a few years ago but the step to remove the directory worked for me.

http://northwestspatial.com/wp/?p=395

Change to your home directory in the terminal, if you need help with the terminal see the Ubuntu documentation 

 

~cd

ls -la

sudo rm -Rf .qgis

 

What these commands will do is delete a read only file that is put on your computer during installation preventing you from being able to download plugins. There is a more detailed explanation in the link.

 

To download the sextante plug-in:

If you want to use all the parts of the sextante plugin, make sure you have grass installed: http://hub.qgis.org/projects/quantum-gis/wiki/Download and make sure you have SAGA installed. You can get SAGA from the software center or online http://www.saga-gis.org/en/index.html.

If you are getting the error that you are missing psycopg2 you have two options

First try and download it from the software center

Screenshot from 2013-07-17 13:57:08

 

Then in the terminal:

sudo apt-get update

Then open up Qgis and see if you are able to get the plugin.

 

If this does not work for you and when you try and download from the software center it give you an error then here is the process to get around that

In the software center look for the synaptic package manager

Screenshot from 2013-07-17 13:59:11

 

 

What is allows you to is download any updates or repositories needed as a sudo user with a GUI interface

In the search box look for the update: I just typed psy and it came up in the list

Screenshot from 2013-07-17 14:01:11

 

Click on it, check mark for installation and then Mark all upgrades

 

Then in the terminal

sudo apt-get update

Then open Qgis and the plugins should be available.

If you have any questions please feel free to post in the comments below.