This is an example of how to use Knitr for doing historical data analysis and writing.
Text that is outside the code block is just ordinary text. You can use it to explain what you’re doing or to write an article.
But text that goes inside a code block is run by R. For example, here we load the historydata package and display one of the datasets.
library(historydata)
library(dplyr)
##
## Attaching package: 'dplyr'
##
## The following objects are masked from 'package:stats':
##
## filter, lag
##
## The following objects are masked from 'package:base':
##
## intersect, setdiff, setequal, union
us_state_populations
## Source: local data frame [983 x 4]
##
## GISJOIN year state population
## 1 G090 1790 Connecticut 237655
## 2 G100 1790 Delaware 59096
## 3 G130 1790 Georgia 82548
## 4 G240 1790 Maryland 319728
## 5 G250 1790 Massachusetts 475199
## 6 G330 1790 New Hampshire 141899
## 7 G340 1790 New Jersey 184139
## 8 G360 1790 New York 340241
## 9 G370 1790 North Carolina 395005
## 10 G420 1790 Pennsylvania 433611
## .. ... ... ... ...
Now I can create a plot inside another code block:
library(ggplot2)
ggplot(data = us_state_populations,
aes(x = year, y = population)) +
geom_point()
## Warning: Removed 1 rows containing missing values (geom_point).
This would be a good place to explain what that plot means.
Now I can click the “Knit HTML” button in RStudio and get a document with the plot embedded. Then I can click the “Publish” button to get a document to share.