45 lines
1.2 KiB
Markdown
45 lines
1.2 KiB
Markdown
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## README
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## About
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This is some R code for the paper [Labor, Capital, and the Optimal Growth ofSocial Movements](https://nunosempere.github.io/ea/MovementBuildingForUtilityMaximizers.pdf)
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## Structure of the code.
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1. `Variables.R`: Contains variables
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2. `Transition dynamics.R`: If we know our system at time t, generate an approximation of our system at time t+stepsize.
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3. `Forward Shooting.R`: Carries out the forward shooting.
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4. `ReverseShooting.R`: Nonfunctional. Ignore.
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5. `Plotting.R`: Generates graphs of the results
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## How to run
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Open files 1.,2.,3., and 5. in an IDE for R, like RStudio. Run them in order. For `Plotting.R`, add or create the directory in which you want the graphs to be generated, making sure it has suitable permissions.
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## Gotchas
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Using a very small stepsize runs into floating point errors. Consider a stylized example:
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```r
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options(digits=22)
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dx <- 10^43
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numsteps <- 10^7
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stepsize <- 10^(-3)
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## Example 1
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x <- pi*1e+60
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print(x)
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for(i in c(1:numsteps)){
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x <- x+dx*stepsize
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}
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x == pi*1e+60
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print(x)
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## Example 2
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x <- pi*1e+60 + numsteps*stepsize*dx
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x == pi*1e+60
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print(x)
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```
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The two examples should give the same results, but don't.
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