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OpenStreetMap: Operation Cowboy

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…and now I’m stuck with Kid Rock’s Cowboy song in my head. I had planned on doing something in Chattanooga and time has grown too short. So I’m most likely going to pick an area I’ve been to (maybe where my dad grew up) and work on the map. So – get your 10 gallon hat on and stay up as late as you can – in my case maybe 1 or 2 if I’m good.

 Operation Cowboy:Nov 23rd-25th 2012

This a training event. Helping people learn more about editing OpenStreetMap editing is an important part of the mission. Whether it’s your very first edit, or you’re swapping power mapping pro-tips, please come along to meet and work with other OpenStreetMap friends face-to-face!

The mission is to make simple improvements to data in the U.S. This is a an “armchair mapping” project, meaning we are seeking to make simple improvements using aerial imagery, and refining the low quality imported data. The U.S. is a good part of the map to do this. We can safely make these kinds of improvements in many areas without too much danger of disturbing valuable on-the-ground mapped contributions, but please be aware of armchair mapping guidelines, and seek assistance if you are unsure.

Types of armchair mapping edits to make in the U.S.

  • TIGER fixup – This is the main information resource to refer to, on the kind of data fixup that is required. TIGER is the original data import of every road in the U.S. it is of widely varying quality in different areas, with pockets of extremely poor alignment, and newer residential developments being missing. The TIGER Edited Map shows where data has not been touched since the original import.
  • MapRoulette – A fantastic new tool which will be very useful for Operation Cowboy. It jumps you to random connectivity bug, but it’s important to note that many of these are also landing you in an area of low quality TIGER data, so while it’s quick to fix the connection problem, you can spend much longer fixing up the surrounding area.
  • NHD – It’s worth understanding the nature and limitations of the Hydrographic data (rivers) which is another import of dubious quality. It’s not hard to find areas where large rivers are missing or broken and failing to show up on the map due to data bugs, even near populated areas.
  • GNIS – There has been an import of nodes representing schools, hospitals, parks, cemeteries, lakes, and several other types of features from GNIS. This data is usually accurate although there are cases of non-existant/closed-down features being imported. As an armchair mapping task though, it’s usually helpfully to spot features in the imagery and convert GNIS import nodes to areas (copying over all tags) See USGS GNIS#Converting GNIS Nodes to Areas

Kennesaw State University GIS Day Nov 15 2012

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Dear KSU Students, Alumni, Faculty & Geospatial Community,

Another GIS Day is nearly upon us in this dynamic world of spatialness!

Kennesaw State University is again hosting their Annual GIS Day and you are cordially invited to attend.

The event will be held on Thursday, November 15, 2012 between 6:30 – 8:00 pm in the Leadership Room of the Carmichael Student Center (2nd floor next to Card Services).

This year’s event will include many spatial festivities. There will be a Google Earth Limerick Challenge, faculty, student, and GIS community presentations, and a couple Google Earth related events. In addition to these presentations and challenges, the new GIS website will be unveiled. Additionally, GIS certificates and awards will be presented (including the Alumni Award and GIS Community Award) in addition to the many event gifts and prizes (such as t-shirts, GIS goodies, and the like). There will be customary food and drink available to all attendees, and free parking for those who RSVP.

Finally, there will be an informal post GIS gathering at Mellow Mushroom after the event for those attendees who wish to continue their conversations beyond the time on campus.

On behalf of Kennesaw State University and the Geography & Anthropology Department, we hope to see you all there!  Map Happy!

Commercial QGIS Support

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So here comes the Great Experiment. Software Support.

I’ve been a 19 year veteran of watching ESRI produce software. Probably 90% of my customers are ESRI based. The other 10% can’t afford a GIS system due to budget. As an ESRI Business Partner I convinced some of the 10% to make the investment. Over the last year I’ve been working with Open Source Software and have decided to branch out. So I dropped my ESRI Business Partner Status and I’m now working openly with Open Source GIS software and ESRI Software. As a GIS business I’m feeling a bit more robust than I was last year.I’m working with more data formats and working with databases (notably Postgresql/PostGIS) more. I’m also working with data – because no matter what you do with ArcGISOnline, or Web Maps, or whatever it’s the data that matters.

To that end I’ve been working on a support page with different options. As was often said in my favorite Chinese restaurant: If you don’t find something you like – we’ll make it.

QGIS has turned into my new favorite software package. So I’m now offering paid support for an open source software package. Some companies are hesitant to use Open Source GIS packages because you don’t have someone to call for support. If I fall back to the old 80/20 rule – I can argue QGIS can do about 80% of what ArcGIS does – in particular ArcView. There are things that are missing but they are few. So what do you get:

  • Cost is $500 dollars for up to 5 installs (computers) of QGIS (How will I know – I won’t).
  • Newsletter and Access to the support website
  • Email Support
  • Phone Support during core business hours
  • Includes a discount on our Introduction to QGIS Class.
  • Time Frame is one year.

More importantly some of this money goes back to QGIS. So your use of the software is going to help the QGIS progress and develop. This is something I’m still feeling out and working on so there will be changes along the way.

Anyway – let the fun begin.

Python and Iterating in ArcGIS

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So yesterday’s post got quite a few views. Someone asked “…but you said you could do this in python”. Since I couldn’t sleep last night I did it in Python.

I’ve had this long running discussion in my head “So What are you good at…” . I can easily list the things I’m not: electrical, plumbing, carpentry, and programming. I like programming. It’s fun. When I started using ArcInfo oh-so-many-years ago you had to know AML or you were going to not have a lot of fun. I hated Visual Basic just enough to not go in that direction when this version of Arc we all know and love came out. I learned perl. Then started this long running infatuation with Python. I use it just enough to be dangerous.

In yesterday’s example you had a watershed you needed to separate. We did it in Model Builder. Today – Python. Instead of an iterator we declare a Search Cursor. I won’t go into all the ins and outs of python formatting or why you type pythong at times when you mean python. I will encourage you to read the ArcGIS help. There are a lot of good examples of how to use python to make your life easier. Python is more than just an ArcGIS tool. You can learn it and then step into ArcGIS and still be lost (or at least I am) trying to learn all the functions and ways to do things. There is no doubt a better way to do what I am going to show you.

You need to separate out the watersheds. Open up a python window….and start typing. I assume at some point you’ve been curious enough to dump a model into python. My phrase of “start typing” is misleading – you have to know what to type.  Location of the Python icon is below.

Location of Python Icon

It takes me a while usually to get “in the mood” and I start off making mistakes.  Lots of mistakes. The thing you need to do is declare a search cursor. Locate the Field and loop through the results. It’s half art.  The nice thing about the python window is you can load files into it and save information out of it. It will also prompt you along through the help window. Eventually I got tired of making mistakes.

Python code
I'm awesome

I saved what I was doing into a text editor and made changes and load these back into a window. Expressions are a pain. There are too many quotes and double quotes and what not to make it fun. I always forget. I always have to go back and think and look at examples. Eventually – success! Here is what I ended up with (documented for your enjoyment)

import arcpy #declare a cursor rows = arcpy.SearchCursor(fc) #Loop through the cursor for row in rows: #Grab the Field huc = row.HUC_10 #Build an expression Pre = '\"HUC_10\" = ' #Format the variable to get it in Quotes Post = "'%s'" % huc #build the expression expression = Pre + Post arcpy.Select_analysis(fc, "C:\\temp\\watershed_" + huc + ".shp", expression)

 

So what did we learn here?  You can do this in Python if you’re not scared to type. You can save it and re-run it (like model builder) and it’s another tool to get you an answer. It took me a bit longer because I had forgotten about formatting the variables to get quotes and SQL all straightened out. I have no doubt there is a better way to do this.  Also – if you know your Arc Python lingo – it takes about the same amount of time as model builder – maybe less. Since I forget some things it took me a bit longer.

Know your data and your tools. Have some fun.

 

 

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