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You can use the double tape to store decimal numbers.

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So far, we used the end long variable to store whole numbers.

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I want to emphasize the word hole because you cannot store decimal values with Ent. or along.

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The entire variable is used to store small hole numbers and the long variable can store big hole numbers.

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So in this video, we're going to use the double tape to store decimal numbers.

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First thing I'll need you to do is create a new class by yourself inside the section to project create

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a new file named Decimals Java and inside the decimals class.

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Make sure it has the main method.

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You can store decimals in a double variable, you can't use Int or long to store decimals, although

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we can do so in a double.

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And there are three things you need to right to define a double.

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You have to specify the double type, which says that this variable is meant to store decimals, the

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variable name, which in this case is price and the decimal value that you want to store.

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This code creates a variable called price, which stores a decimal value of three point ninety nine.

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So when the decimals class, we're going to create a variable named percentage double.

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Percentage.

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Is equal to fifty five point seven.

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Now we're going to print this percentage inside a string system, dart out dot print line will say in

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2020.

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Disconnect the string, embed, the percentage will say in 2020, some percentage.

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Of the world's population is urban.

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OK, compile your code and run it.

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Looks good.

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The variable percentage stores the decimal fifty five point seven, and you printed the value from within

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a string.

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Easy stuff.

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Back to our quote, I'd like to emphasize that you cannot store in decimals inside an Int or long variable.

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If you try to do it, you'll get an error.

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Let's try to change percentage to Annette.

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Compile your code.

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And we get an error in this line of our code and variables can only store whole numbers, so change

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the variable back to a double.

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And clear the output.

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Now, what happens if we reverse this and try to store a whole number in a double variable?

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Let's find out double.

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Dividend, we're going to create a double variable dividend and set it equal to 25.

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And we'll print it system dot out, dot print line dividend.

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Compiling our code and running it.

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And it prints it as a decimal double variables are special because even if you don't express the number

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as a decimal double, it's going to store it as one.

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In this case, the dividend variable stores the value twenty five.

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But since dividend is a double, it stores it as a decimal 25 point zero.

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With that being said, it's imperative that you always use double for math calculations if precision

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is important.

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You need to have decimals.

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So create a variable named deviser double divisor.

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And set it equal to two.

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Then we can divide both numbers using the division symbol, the front slash, so inside the Prince Mint

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will print the result of dividing both numbers.

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And as expected, 25 divided by two is twelve point five and dividend is a double edged sword.

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25 as a decimal, 25 point zero, the divisor double variable stores, two as a decimal 2.0.

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And when you divide a decimal by another, the result is a decimal value.

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All right, with that being said, avoid using int or long variables for math calculations.

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If you divide two whole numbers, the result will always be a whole number.

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This may not seem like an issue, but make dividend and deviser integer variables instead into dividend

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and divisor.

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Now, run that.

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And I hope you can see that the result is not correct, 25 divided by two is twelve point five, not

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12.

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The dividend variable stores, a whole number 25, the divisor variable also stores a whole number,

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and if you divide two integers, the result is going to be an integer.

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Int isn't able to work with decimals.

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So what it does is it cuts off decimals from the results and keeps only the integer in math.

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You need decimals to stay accurate.

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So always use double variables in math operations because double treats every number as a decimal and

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keeps the math accurate.

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So going to switch this back to double's.

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All right, finally, we could make the print statements more interesting to end off on a high note.

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So what we're going to do is embed this result in a string as well.

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We're going to print the dividend disvalue.

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Divided by break the string.

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The divisor value.

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Is equal to.

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The arithmetic result of dividing dividend by divisor.

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Run the code.

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OK, let's add some space between the word dividend and the first string recompiling the code.

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We can wrap this lesson up with these rules, use into historical numbers, use long to store very large

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hole numbers and use double to store and work with decimals.

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And this lesson you learn to use double to sword decimal values, you created a double variable that

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stores a percentage and then you printed the value for more than a string.

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That was pretty easy.

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And double stories, any number as a decimal, even if you don't express it as one and decimals help

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keep the math accurate, that's why you should always use double for math, avoid using whole numbers

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in math calculations, because if you divide two integer values, the result is going to be an integer

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value.

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It cuts off the decimal and keeps only the integer, which is not correct.

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So to avoid mistakes, no to use int to store whole numbers long, to store very large hole numbers

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and double to store and work with decimals.