# Commits

committed efb6bef

initial import

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• Parent commits c18e1c7

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`+* hello world`
`+Start the R interpreter and print the string "hello world"`
`+* hello.world function`
`+Create a function called hello.world that does what you did manually`
`+in the previous exercise. `
`+* create an anonymous version of the same function`
`+* use Google to figure out what R's rules are for naming variables and functions`
`+* hello(name) function`
`+Create a variant of the previous function that accepts a `name``
`+parameter and prints "Hello Mary", "Hello Lamb", etc. `
`+`
`+Hint: you'll need to figure out how to concatenate/join strings`
`+* hello(name) with a default argument`
`+Give the `name` argument a default value.`
`+* create a `vector` of the following strings and assign it to a variable`
`+"Mary", "had", "a", "little", "lamb"`
`+* use help.search to find a function that can convert each element in that vector to uppercase `
`+* find a function that will give you the length of the vector`
`+* figure out the syntax to get the third element in the vector`
`+* create a function that applies another function to each element in a vector`
`+* find a function that will create a sequence of integers`
`+This is like the `range` function in Python.`
`+* use that function and the `matrix` function to create a 4 x 5 matrix of the first 20 natural numbers`
`+* figure out the syntax to get the matrix element at row 2, col 3`
`+* multiply every element in the matrix by 3 `
`+* find a function that gives you the dimensions of the matrix`
`+* convert this matrix to a vector`
`+* create a Boolean matrix of the same size `
`+... that indicates whether the elements in our first matrix are > 13`
`+* use the Boolean matrix to take a subset of our first matrix`
`+... where the condition is true`
`+... and where it is false`
`+* what is the type of the subset`
`+* figure out how to create a random sample of 100 integers`
`+* take a random sample of five elements from your first matrix`
`+* find the built-in dataset `swiss` and the help information about it`
`+* what are the `type`, `dimensions`, `structure`, and `dimension names` of this dataset`
`+* figure out how to access each column of this dataset individually`
`+* show the first and last six elements of this dataset`
`+hint: there are built in functions that will do this for you`