bsmall2 Learning Racket

Emacs

DrRacket is good for visualizations. Emacs helps me do the preparatory thinking and editing, but adjusting plot details is fun in DrRacket. The .csv data used for this post's visualization is below the code.

DrRacket Screenshot: Visualizing Energy Use and State Populations

Using the same wikipedia data as a previous script and post (fn:1), this is a reproduction of another of Hiroaki Koide's小出裕章の graphs. It was good brain training and attention strengthening to figure out how to do this with Racket Plot.

Unjust Energy Use and Country Population Visualization

Reproducible research techniques with DrRacket could contribute to a good, exploratory education. Learners can hack the script, make lists of countries to label, adjust the sizes of the plot and create something that they feel is worth printing out to thinking about...

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The Racket language lets me enjoy scripting, so that the adding machine does work that would be repetitive drudgery the human being. Automating “the boring stuff” is what computers are for.

This little script makes it easy for me to share pictures that have been batch-converted with Racket. (fn:1) I have a script that takes a text file of image basenames (such as “010”) with sentences and generates an html page to print out as a worksheet. The worksheets have been working well for our GDM (Graded Direct Method) class, but uploading the pictures with Markdown to WriteFreely is going to get more cumbersome as the sentences get longer and more numerous.

An hour or two of focus this evening let me WriteFreely blog the fourth lesson in a smooth manner. (fn:2)

Dr Racket Screenshot of text to markdown script

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宮崎県立都城農業高校の冷水機

A water fountain at Miyakonojyo Agricultural High School reminded me of a Financial Literacy lesson idea. I used to do this with emacs org-mode tables and it was fun. But now, with Beginning/Basic Education in the back of my mind, I try to do everything in DrRacket (and then use emacs to get a shell script to work).

Water Fountain Financial Literacy with DrRacket

Code

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Before posting pictures to Diaspora*, pixelfed, or writefreely I often select the worthwhile parts in Gimp. After selecting the worthwile part of a pictures, if the part is still larger than 700 pixels (for Diaspora*) or 1400 pixels (for pixelfed) I try to re-size the snippet before uploading. Re-sizing seems like a decent, or “ethical”, thing to do. I haven't been able to donate to some of the servers that make my free SNS accounts possible, and I hope to avoid burdening any viewers. Resizing before uploading lessens burdens on servers and devices (I imagine). Besides the general ethical reasons, some servers have volume limits, so keeping image sizes down should let me share more photos before approaching my limits.

I re-size the image in Gimp before exporting the photo to an “edited” folder. The photo manager shotwell organizes photos in year/month/day directories. So one day a program could go through the directories created by Shotwell, find all the edited pictures, and organize them in a useful way. In the meantime, I just want save a step in Gimp. With this Racket script I can just save selections to the “edited” directoy without the extra step of resizing the image canvas. It will save time to avoid working with menus…

DrRacket Screenshot: Resize jpg files script

This time I got the script working in DrRacket first, then made an executable script in Emacs…

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