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Measles by the Numbers

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  Generated by ChatGPT 5.2 On Feb. 28, 2026, I downloaded data for reported weekly US measles cases by rash onset from the CDC website  https://www.cdc.gov/measles/data-research/index.html  into a file named  measles_data_weekly.csv . I plotted the data using R. library (tidyverse) df_by_week <- read_csv ( "/mnt/g/measles/data/measles_data_weekly.csv" ) > head (df_by_week) # A tibble: 6 × 2 week_start cases < date > < dbl > 1 2022-01-02 0 2 2022-01-09 0 3 2022-01-16 0 4 2022-01-23 0 5 2022-01-30 1 6 2022-02-06 0 > # plot weekly data ggplot (df_by_week, aes (x = week_start, y = cases)) + geom_bar (stat = "identity" , color = 'blue' ) + labs (x = "Date" , y = "Cases" , title = "Measles Cases by Week" ) What happened in February 2025? One thing was that a new administration was in place in Washington with an  anti-vax ...
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SECD and Functional Lisp

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Image generated by Claude.ai The SECD machine  is a virtual machine designed to be a target m platform for functional programming languages, in particular Lispkit Lisp. the SECD name comes from the four basic registers of the virtual machine: stack, environment, control, and dump. Three of the registers typically act as stacks: stack, control, and dump. The environment register usually contains an associative array.  The SECD machine was originally described by Peter Landin in " The Mechanical Evaluation of Expressions " in 1964. The version I am considering here is described in  Peter Henderson's book Functional Programming Application and Implementation [1980]. It's out of print. You can find used copies for sale online.  S-expressions Each cycle of the SECD machine updates one or more of the registers. An SECD program is an encoding of a functional program into machine code. In the SECD representation, each operation is represented as a number. The SECD machine o...
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