In dtkaplan/checkr: Facilities for checking R submissions in tutorials

library(learnr)
library(checkr)
knitr::opts_chunk$set(echo = FALSE)
tutorial_options(exercise.checker = checkr::check_for_learnr)
# tutorial_options(exercise.checker = function(...) cat("Bogus checker\n"))

NEED TO UPDATE THIS TO READ IN THE SYSTEM FILE WITH THE checking functions.

Using rep()

a. Create a vector named Id that has contents 1 1 1 2 2 2 3 3 3 4 4 4. Use the rep() function to do this.

Id <- rep(1:4, each = 3)

1:4

rep(1:4, .... = 3) 

1 # There must be something in this chunk.

checkr:::rep_1245(USER_CODE)

b. Create a vector named Letter that contains "a" "b" "c" "a" "b" "c" "a" "b" "c" "a" "b" "c"

Letter <- rep(c("a","b","c"), each = 4)

c("a", "b", "c")

rep(...., length.out = 12)

1 # chunk can't be empty

checkr:::rep_abcd(USER_CODE)

c. You've constructed Id in the previous exercise. Copy the statement you used to do that into this code block. Then create two more vectors: 1. x which will be evenly spaced numbers between 1 and 43. x will have the same length as Id. 2. y which will be similar to x, but will consist of evenly spaced numbers between -20 and 0.

Once you have constructed `x` and `y`, make a data frame called `df` that contains `x`, `y`, `Id` as columns. The variable names should be `x`, `y`, and `Id`.

```r

Id <- rep(1:4, each=3) x <- seq(1, 43, length = length(Id)) y <- seq(-20, 0, length = length(Id)) df <- data.frame(x=x, y = y, Id = Id)

```r
Id <- rep(1:4, each = 3)
x <- seq(1, 43, along.with=Id)
y <- seq(-20,0, along.with=Id)
df <- data.frame(x = x, y = y, Id = Id)

#USER_CODE <- "Id <- rep(1:4, each=3); x <- seq(1, 43, length = length(Id)); y <- seq(-20, 0, length = length(Id)); df <- data.frame(x=x, y = y, Id = Id)"
checkr:::df_abcd_1234_x_y(USER_CODE)

dtkaplan/checkr documentation built on May 15, 2019, 4:59 p.m.