Hello everyone.
Welcome to the PI exercises overview lecture.
In this brief lecture we're going to quickly go over the exercise questions and how to approach them
.
Then you'll go ahead and perform the exercises see if you can solve them.
And after that we'll have a lecture on the solutions.
Let's go ahead and jump to the exercise notebook and quickly go over the questions.
All right.
Here we are at the PI exercises notebook which you're going to go ahead and do it.
Just answer the questions or follow the instructions in bold and you'll see that there's actually output
arrays for you or output answers for you which are the answers you should get.
Keep in mind that if you actually run the cell that has the direct output below you will overwrite the
output.
So for instance if you're saying create an array of 10 zeros hopefully you remember from the lectures
how to do that.
But if you have code here such as print hello and run that code you will no longer see this output.
So keep that in mind as you're running through this exercises.
All right.
So basically we'll start off with asking you how to create some arrays some array of integers some array
of identity matrices three by three Matrix etc. Some random number matrices and then I'll ask you to
create this following matrix.
So keep in mind that you should insert cells here in order to not delete the output.
Then I'll ask you to create an array of 20 line nearly spaced points between 0 1.
So just go ahead and follow the instructions here and pay careful attention to not overwrite the output
.
If you're not ready to overwrite it yet then we'll talk about pi indexing and selection where it I'll
give you a few matrices.
In this case it's just actually one matrix.
This one through 25.
That's a five by five matrix.
And I will ask you to grab chunks from that matrix and notice here I have given you an extra cells since
these are a little trickier and you need the reference.
So go ahead and write your code here and that reproduces the output in the cell below and be careful
not to actually write your code here.
Otherwise you'll overwrite the output that you're trying to replicate.
And if you get it wrong the first time you don't remember what you're actually trying to answer.
So again just write the code here in these cells.
That way you don't overwrite the output itself.
OK.
And then through those exercises you're going to be trying to grab the chunks shown here as the answers
.
Then in that same matrix or that reference that same matrix you'll get the sum of all the values get
the standard deviation of all the values and then get some the sum of all the columns in that matrix
.
All right.
That's it.
Best of luck.
And coming up next.
Are these solutions to these dumb pie exercises.
Thanks everyone and I'll see at the next lecture