Grabbing a Single Row
In addition to Numbers, Strings, Booleans, Images and Tables, Pyret has a data type for an individual Row.
Open the Animals Starter File and click "Run". In the Interactions Area (right), type animals-table. Hit "Enter" to see the default view of the table.
Then type row-n(animals-table, 2) and compare the result to the table.
1 Write the code that generates the first row of the table.
2 Explain what the second input to row-n means, in as much detail as possible.
Grabbing Multiple Rows
3 Type first-n-rows(animals-table, 5). What happens?
4 If we wanted a table of the first 3 rows of the animals-table, what code would we write?
5 What is the Contract for first-n-rows?
Defining Values
Pyret lets us define values that we want to use later. We can define any kind of values we like!
6 If we tell Pyret that x = 4 * 2, what would you expect to get back when you type x + 1?
Test it out by typing x = 4 * 2 into the Interactions Area, hitting "Enter" and then typing x + 1.
7 Try typing gt = triangle(50, "solid", "green") and hitting "Enter".
What happens?
Now type gt. What do you get back?
8 Explain what is happening on Line 14 of the Animals Starter File.
9 On line 16 of the Definitions Area, add a new definition called my-pet, which is defined to be your favorite animal.
code:
10 Add a new line at the bottom of the Definitions Area, define first-3 to be a subset of the first 3 rows of the animals-table.
code:
★ What happens when you type first-n-rows(sort(animals-table, "pounds", true), 5)?
Note: In this case, the output of sort(animals-table, "pounds", true) is the Table first-n-rows is taking in!
★ ★ See if you can figure out how to compose the code that would generate a table of the 10 oldest animals!
function-name (Table, Number)
These materials were developed partly through support of the National Science Foundation, (awards 1042210, 1535276, 1648684, 1738598, 2031479, and 1501927). 
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