WEBVTT

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Arithmetic expansions in Shell.

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The shell allows arithmetic to be performed by an expansion, so this allows us to use the shell prompt

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as a calculator.

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So, for example, let's do this echo, and now we're going to do here braces, oops, braces here.

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And for example, two plus two.

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And as you can see here, we got an four.

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So arithmetic, exemptions, expansions, you can be used like this, for example.

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You will firstly, let's actually use our grommet.

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So you will use the expansion, the dollar sign.

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And after that, two braces here and you write your expression here expression.

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Here.

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Now use two curly braces again.

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And after that, that's it.

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So, of course, don't forget to write your echo command before then.

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So we here we have the just an empty space.

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So where expression is an arithmetic expression consisting of values and arithmetic operators.

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So arithmetic expression expansion supports only integers, whole numbers, no decimals, but can perform

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quite a number of different operations.

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So for example, it can be used for addition for subtraction, for multiplication, for division.

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But remember, since expansion supports only integer arithmetic, the result is going to be always,

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always.

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Integer.

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Integer.

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Output.

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And it also supports modulo which is which simply means reminder.

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And we also have exponentiation, which is two here.

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So we also have an exponentiation here.

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So spaces are not significant in arithmetic.

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Operations and expressions can be nested.

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For example, here, let's do another example like this.

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So for example, let's write Echo.

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Here.

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So we will write the nested expression right here.

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And after that you call braces again after dollar sign.

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And now five multiplication two.

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Not this isn't a multiplication.

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Actually, it's exponentiation.

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And after that we will use that three.

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And here, let's see the results here.

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So single parentheses.

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This is our results here.

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So a single parentheses may be used to group a multiple subexpressions.

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With this technique, you can rewrite the previous example and get the same result using the single

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expression instead of instead of two.

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And we can also write the strings and mix it together.

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So Echo, for example, five divided.

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Divided by two equals.

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And after that, we will enter our division here.

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So five divided by two and here and as you can see here, five divided by two equals two.

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Yeah, that's actually not a Yeah, that's actually true.

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But and I said earlier that this expressions in echo.

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Supports only integer arithmetic and the result is going to be integers.