Friday, June 23, 2017

Mod 5: DC Crime Mapping

This week we started the Homeland Security section of this course. I was required to turn in two maps of Washington DC. One being a proportional symbol map showing DC police stations that are in proximity to crime occurrences. I first had to use a xls file to create a shapefile to map the locations of the DC stations. Then i could create a multi-ring buffer and count the occurrences as they extended out from the police station. I performed a spatial join from the multi-ring buffer. From the spatial join, I could calculate the ratio of total crimes to crimes in proximity to police stations. Here is the final map:

The second map was a kernel density map to show the density of individual crimes that occurred within Washington DC. I used the kernel density tool for three crimes, burglary, homicide, and sex abuse crimes. I used a cell size of 73 and a search radius of 1500. Here is my second map:

Wednesday, June 21, 2017

Mod 5: Geoprocessing in ArcGIS

This weeks assignment was to create features using models and scripts. The first task was to create a model to clip a feature. Next, I took that output and selected attributes from the clip. I, then, used the selected attributes to erase them from the original clip. The result was polygon with a bunch of funky polygons within it that had been erased. Once i had a working output, I exported the model as a Python script.
I tried to run the script in PythonWin and was met with a bunch of errors and used the given text to clear these errors up. After much trial and error, no pun intended, I had a working script and I just remembered that I left the last line in the script that says print "success" if it worked properly. Hopefully, I will not be punished for that.
Lastly, I took this script and sent it back to ArcGIS to use it as a script tool. For the first time in this class, I felt comfortable with the lab. I understand ArcGIS and being able to see how a script creates data that can become a visual aspect on a map is fascinating. Here is a screenshot of an output as a map feature.

Saturday, June 17, 2017

Mod 4: Hurricanes

This week, our assignment was to create two maps. The first being a map that shows the path of Hurricane Sandy. We were given an excel file (contained coordinates and attributes) and had to plot the x,y points. With the points created, we could draw a path with the point to line tool. With the attributes in the excel file, I could add them to the map showing wind speeds and pressures.

The second map was to do a damage assessment of when Hurricane Sandy made landfall in New Jersey. I used aerial raster mosaics, pre-storm and post-storm. I used the Effects Tool to go back and forth between the images and determine where the damage had occurred. Next, I created point for each parcel and gave attributes to each point (level of damage). 

Wednesday, June 14, 2017

Mod 4: Debugging and Error Handling

The weeks exercise was on debugging scripts. We were given three scripts that had errors and were required to fix them to allow them to run. The first one contained syntax errors and was fairly easy to deal with. The second one dealt with exceptions and we were required to debug them, mainly attribute errors. The last script was leaving the exceptions in and using try-except statements to continue with running the code and allowing the error to remain. Here is a screen grab of the results of each of the three scripts.

Sunday, June 11, 2017

Mod 3 Natural Hazards: Tsunamis

This weeks assignment was long and challenging but also fun. The assignment was to create a map that shows the extent of the hazards from the Japan Tsunami and the radiation from the Fukushima Power Plant melt down that was caused by the tsunami. There were numerous learning objectives to complete this project. The first was setting up a geodatabase to organize the data being used and further organizing with datasets within the geodatabase. I used multiple tools to clean and prepare data to be used such as converting x, y data, building raster attribute data, buffer and multi-ring buffers. Next, I used the model builder to utilize raster data to find areas that needed to be evacuated.
Once that data was created, information was clipped to find the extent of the area impacted. Here is an image of the final map:

Wednesday, June 7, 2017

Mod 3: Python fundamentals Part 2

This weeks assignment was on loops and adding comments. I failed miserably and was not able to finish the assignment. I can add comments to my script successfully.

Sunday, June 4, 2017

Mod 2: Natural Hazards, Lahars

This week we used the hydrology tool to map where a lahar could happen on Mt. Hood in the event of an eruption. This exercise was interesting because we used DEM data to create a river vector shapefile. Once it was a vector file, we could then buffer it to show the extent of the lahar hazard around Mt. Hood. I enjoyed this exercise because it shows how GIS can be used in the real world. here is my final map: