Monday, April 28, 2008
It's an awesome tool
Wednesday, April 23, 2008
Wednesday, April 2, 2008
Note: When using the Dissolve ALL Function with a buffer. Buffers created with the dissolve All option form a single feature called a multi part polygon. AKA the attributes go to the standard 4 objectid, shape, distance, shape length
To Clip a spatial attribute based within a layer you must select that attribute. I first created a new layer.
To Create a New Layer: (you could go to selection menu –Set Selectable Layers, then on the Tools toolbar click the icon to ‘Select Features.’ And click on the one you want, then right click on the layer Selection- create layer from selected features.) TADA
Then go to Arc Toolbox - Extract –Clip – Remember you are Clipping one layer based on another, the input is the layer that will be changed based on the output layer TADA
Go to: Arc Toolbox – Generalization – Dissolve – Input Features (the input layer to Dissolve) Then select the attribute you would like to aggregate
Are you still with me? Ok, so snapping is a great way to georeference. So, you have your known and unknown data, right? Using the editing tool bar click the drop down to ‘start editing’note: you can only edit one data frame so if given the choice click on the one you want to edit. Using the same drop down set your ‘snapping,’ click on what you want to snap, in our case it is roads and trails. Now you want to use the edit tool to (Task) create a new feature in this case, and here we are tracing along the lines of the trails- The goal here is to make a vector layer of trail data. You can double click when you're finished and the feature will highlight. Then you can go into the attribute table and add data.
Trace tool Will allow you to trace along a feature that is highlighted, exactly copying it
How to highlight a feature click on it with your edit tool
What kind of coordinate system, what is the map projection, what spatial reference that our data is in? Go to Arc Catalog- file folder- metadata
Or Contents – right click properties- XY Coordinate System You can check out the projection.
Now that the trail map has been georeferenced, the next step is to use it to create a vector layer of the trails complete with attribute information.
So we go to the Bent Creek Folder and Right Click New- New File Geodatabase
Then we need to create a new feature class for the database so we right click on the geodatabase create a new feature class. Here you specify what kind of coordinate system your data is going to be in.
Monday, March 31, 2008
Using the View drop down and going to Toolbars- Georeferencing toolbar. This allows us to assign real world coordinates to our raster data, to a image that does not have real world coordinates, using control points.
Starting in the display window layer of our real world coordinates we ‘fit to display’ our new data to display an overlap. Here we can reference non real world to real world starting with the unknown using control points. You have to use more control points if your map is not very accurate.
We create a world file by Updating Georeferencing
Wednesday, March 19, 2008
Here I am selection attributes by location, looking for the best spot to place my client's new business. We want it to be close to a business center, and because it's a pricey shop we need it to be in an area with a high density of people with a alot of money. The second picture showsthe final location chosen.
This map focuses on abandoned pit mines that have high concentrations of heavy metals that could cause concerns about safety. I have identifies these sites based on the actoin required to clean the sites. I have used a 'join' based on the common attribute feild of IDNumber to add more data.
This was an introduction to selecting by attributes, it's some pretty interesting stuff. So, you are working with a client who is interested in three bedroom houses that are for sale on corner plots. One of the pictures shows all the plots that are for sale selected using a select by location status = y Yes they are for sale
Wednesday, February 6, 2008
Should you define a coordinate system when you don’t know its origin? What kinds of problems could occur?
Walk me though how she narrowed down her search in defining her data for Ohio.
Give me an example of when you would use NAD83 and WTD84 interchangeably and when should you not. Explain.
What is the difference between Coordinate systems and special reference?
Monday, February 4, 2008
This shows a layout view of the area of
disappearance on the Earhart path. We
went into ArcCatalog and dragged the
polygon file on to our World map. Then we
inserted a new data frame using the insert
drop-down, and moved two more shape files
showing the area of disappearance and the
sea floor gradient, and added the flight data.
Wednesday, January 30, 2008
This map is so good looking, I love it.
I think my biggest challenge in 121
will be constantly coming up with
ideas for what information I want
to portray to the viewer. I struggled
with that in this map, and I think
coming up with ideas that can be
enhanced when thinking about
them spatially will be helpful.
Thursday, January 24, 2008
Wednesday, January 23, 2008
Welcome to my blog spot!
This blog spot is aimed at helping me organize my Geographical Information Systems notes, as I embark on a journey through GIS Intro and Cartography at AB Tech.
A little background, I am a recent UNC Asheville graduate student with a BS in Environmental Management and Policy, Minor in Economics. As a student I worked on many environmental advocacy projects. In my last semester I co-founded and directed the new Student Environmental Center at UNC Asheville, that is now located in the Highsmith Uviversity Union. The center serves to educate the campus community on environmental issues through community-based social marketing, energy conservation and efficiency programs while working with state and local governments to better meet their sustainability goals.
I hope to be a part of the solution to Climate Change with a municipality, government, or private industry, as our choices will affect all life on Earth.