A histogram is a very useful construct. It is a chart for displaying how frequent
a given quantity might appear in an otherwise "random" stream of data. It usually involves bars that are drawn in proportion to how
frequent a given number occurs. Histograms are very useful for exposing patterns in a stream of numbers.

Arrays are the perfect data type for creating histograms. In this lesson, we'll again analyze the "randomness" of our random number generator, but we'll make a histogram in the process.

Below is some code that will declare a histogram called `hist`

and initally set the elements from -100 to 100 of it equal to zero. Next,
using the `for c=1,10000 do`

loop, we'll ask the computer to throw 10,000 random numbers. We'll choose each random number to exists,
in variable `i`

, between -100 and 100, the same as the bounds of our histogram, `hist`

. With each random number in variable `i`

,
we'll create a histogram by incrementing the $i^{th}$ element of array `hist`

with each random number.

The last for loop will make a simple plot of the histogram by drawing a line for each "bar" of the histogram. By looking at the histogram plot, what can you conclude about the random number generator?

`i = math.random(...)`

line to add one count to the $i^{th}$ element
of the histogram stored in the array called `hist`

.
Type your code here:

See your results here:

This code will not run! You have to fix the line right after the

`i = math.random(-100,100)`

line to do this:
- Realize that
`i`

now contains a random numnber between -100 and 100. - We are trying to count and log the number of occurrences of these random numbers.
- To track how many times the random number in variable
`i`

occurs, we want to increment the $i^{th}$ element of array`hist`

. - Doing these increments creates a histogram of the random number occurrences.
- So in the line following the
`i = math.random(...)`

line, how will you add one to the current count in histogram element`hist[i]`

?

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