A failed midterm and renewed practice

 We all know that the ArcGIS Pro check did not go exactly as planned for me.  The lesson was learned: listen to the professor when he gives a very basic instruction ("pull in the shape files first").  On the upside, I now know how to change map coordinate systems "from scratch," and I also figured out which map coordinate system I needed to be able to change the map to ("USA Continuous Albers Equal Area Conic").  On the downside, it took me nearly the entire hour to figure out these two less-than-crucial pieces of information, not the most efficient use of my time.

I returned to the lab today, gave myself an hour to retry the midterm, and I did much better.  Of course, I had the advantage of having seen what was expected, and I still didn't finish the whole exercise.  I also am not totally sure that I did what we needed to do correctly.  But here are my first three maps with some questions and comments.  [Edited on October 24: map 4 has now been added below with commentary.]

Map 1 was quite straightforward.  My comment is that I thought I had georeferenced the map fairly well, but apparently I didn't. Adding the navigable waterways as lines showed that my coastline was a bit off.  Another comment is that I continue to struggle with formatting the text in the textboxes; I had practiced this a bit last week, but apparently, that skillset remains lodged in part of my brain that needs more practice to be easily accessible.  (I did find where to format text in textboxes after this exercise!)

Creating the map of the fall line was also quite straightforward although I did wonder whether or not--for analytical purposes--it would be better do create the feature of the fall line within its own feature class or as one feature in the rivers feature class.  (I ended up going with the latter since some of the analysis in the remainder of the check-up seemed to rely on the fall line alone.)    I thought the map would look nicer with the navigable waterways included, so I tried adding them, but then they were not showing up in the legend.  I wonder why not?  I took them out again.

Map 3 took the bulk of my hour, but I think I got there.  As I created the tabular join to be able to create this map, I struggled with a few things: for starters, I did not know that we could join .csv files to shapes via a tabular join, but after trying other options, it seemed like the most straightforward path for what we needed.  As I did so (and validated the tabular join), I got a little bit worried as the validation said, "The input table has 379 and the join table has 2802 records."  After thinking about it, I realized this discrepancy might be OK since the input table (the shape file) had far fewer counties than the join table (total US population by county in 1890, I believe).


I also struggled a bit with creating the population by acreage as I was trying to do this in a new field.  As I tried to add that field, I kept getting this message in red "ERROR 000464: Cannot get exclusive schema lock.  Either being edited or in use by another application or service. Failed to execute (UpdateSchema)."  The ArcGIS Pro site told me this meant that several people may be working on these data at the same time.  I was reaching the hour-mark around this point, so I simply decided to map the fall line against total population, then I realized that I could normalize by acreage since the tabular join had been completed.  Success!  (Success?  Is this how to do it most efficiently?)

Update on October 24: I returned to the lab today and gave myself 15 minutes to complete Map 4.


This map looks a little longer than the first three, and I suspect I accidentally used a different layout format (maybe A4 rather than letter?).  The good news: I was able to complete this (with an added navigable waterway that I had missed when heads-up digitizing the waterways the first time) with no drama.  I also was able to increase the font size for the title textbox relatively quickly although I still struggle to find that feature.  A few items continue to perplex me:

  • I cannot figure out how to lock in a layout; when I updated my layout for Map 4, all of the previous first three maps came to look identical to Map 4 within the map frame.  I'll be Googling and working on this later this week.
  • I also could not figure out how to make "Join_Count" disappear from the Legend (underneath the primary category in the legend, the number of waterways).  I remember doing this in a previous lab and, again, will be Googling and trying to streamline my ability to do some of these basic formatting pieces.
The bonuses still scare me, so I want to work on charts a bit more this week as well.  Nonetheless, it's reassuring to know that these processes are becoming part of my brain functioning.  Have fun at the conference in Chattanooga, everybody!

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