[MUSIC]
Alright, so so today's lecture is about the debugging tools that are built into R.
So these come with R.
They're not part of any package and they can be useful for kind of
figuring anything out, figuring out what's wrong
after you've discovered there's a problem, right.
So how do you know that there's a problem? So, there are a couple of
indications that R, will produce that that will
give you the sense that there's something going on.
And they kind of, and this is the, roughly the gradient.
And so I think I mentioned this before.
But, basically there are three main types of indications.
The first is a message. And a message is a very tame notification.
It's just an in, it could be a diagnostic message that something happened.
But it could, it could be nothing.
Okay?
And and so the message won't stop your function from executing.
It will just it will print.
There will be a message that gets printed to the screen
and the execution of the function will continue and that's all.
The next level up is the warning.
All right? So the warning is another indication.
Usually, if you're writing a function, you are choosing, you're trying
to figure out, okay, what's a message and what's a warning.
furthermore, or if you're
using a function and you're figuring out well what does that
mean, a warning is an indication that something unexpected happened it's
not necessarily a problem, and may, and many times you, you,
you explicitly want to ignore warnings but there's something unexpected happened.
So the function was expecting one thing, and it got something slightly different.
It wasn't enough to kill the whole thing,
But it was enough to kind of trigger this warning.
So execution of the function will continue if a
warning occurs but you'll get a message after the end,
so once you'll get a message when the function completes execution.
So when the function comes back, when you
get your console back, that's when the warning appears.
So you won't get a warning in the middle of the execution.