Python for Absolute Beginners Transcripts
Chapter: Course conclusion
Lecture: Review: Variables and types
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One of the first ideas that we explored
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were variables and assigning values to them.
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For example, we open the Python REPL
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and we said x = 42.
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In this language, in Python
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you have very little ceremony that you have to go through
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to declare variables and set them up and give them values.
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We don't have to say, we're creating an integer called x
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or a string called name or anything like that.
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No, we just say the variable name equals the value.
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But remember, you do have to keep in mind
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that there is an underlying set of different types
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of variables and data, and they can only interact
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usually, when they're the same type.
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For example, we could take a list
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and combine it with another list
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we could take numbers and do math with them
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we could take strings and combine them
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to make larger strings
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but you can't take a number and a string
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and combine it using the standard operators
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or anything like that and have that work out
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but here we said x = 42 and y = 19.
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These are both integers
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and then we did some math with them
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and what we got back is another integer, 175.
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We also wanted to create some text type data.
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In programming, we now know this is called a string.
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So we're going to say name equals Michael
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and if you were to ask what is the type of name
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it would say it's a string, of course.
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If you try to combine them like I indicated before
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you're going to get some kind of error.
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In this case, type error
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can only concatenate strings, not integers.
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Though we saw we also have to use f-strings
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or formatted strings.
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Generally we want to take different types of data
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and combine them into some kind of final text output
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high, curly, name, and that variable name
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gets plopped in there by Python.
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Looks like you just did math, and it has the value of x
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the value of y, and then you can even put the expression.
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Remember, it maybe makes more sense
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to assign like a z variable for the x + 7 * y
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but just to show you can have actual computation
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and expressions and evaluations in there
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we put that statement in there again
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and we get this, Hey, Michael, looks like you did math.
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42 + 7 * 19 = 175.
