How do i Multiply a BigDecimal by a Double

[s0meb0dy]

yeah i checked but i didnt understand the methods

[Fubarable]

this has nothing to do with beer

Exactly. And this:

i can only use double with the Math.pow(); method

has nothing to do with your problem. BigDecimal has its own power method.

[Fubarable]

yeah i checked but i didnt understand the methods

What don't you understand about them? First of all, do you understand the BigDecimal constructors whereby you can get a String (that holds numeric info) and construct a BigDecimal with it? Please read that section of the API again. If you still don't understand it, then please come on back with a specific question.

[s0meb0dy]

i dont know what to do!!!! i looked at the sight you suggested all day but i dont understand what the method is!!

[s0meb0dy]

public BigDecimal(double val)

what does this mean? how do i use this to change a double to a BigDecimal?

[s0meb0dy]

public BigDecimal(double val)

what does this mean? how do i use this to change a double to a BigDecimal?

[Fubarable]

i dont know what to do!!!! i looked at the sight you suggested all day but i dont understand what the method is!!

Slow down.

First off, have you used the API, do you understand how to use it? If not, you need to get familiar with it as your Java experience will be very frustrating without this skill.

Go to the BigDecimal API here: BigDecimal (Java Platform SE 6)

And find the section called "Constructor Summary". It will show all the constructors available for use when you want to create a BigDecimal object. There's really nothing confusing about them. For instance, there's one that describes how to use a String to create a BigDecimal object, and it's nothing more than this:

public BigDecimal(String val)

To use it, you simply get your String from the Scanner object and create your BigDecimal:

      Scanner myScanner = new Scanner(System.in);

      System.out.print("Enter a Number: ");
      BigDecimal myBigDecimal = new BigDecimal(myScanner.nextLine()); // error if they don't enter numeric data

Next look at the methods section and you'll find one on how to get power called "pow". Please look it over and try to figure out how to use it in a very simple program. If the program doesn't work, please post it here and again, we'll help you.

Luck!

[Fubarable]

what does this mean? how do i use this to change a double to a BigDecimal?

It means that you can convert a double to a BigDecimal simply by passing it into the parameter of a BigDecimal constructor:

double myDouble = 3.0;
BigDecimal myBigDecimal = new BigDecimal(myDouble);

See, nothing to it! :)

[s0meb0dy]

so, trying to understand your post, when you put

BigDecimal myBigDecimal = new BigDecimal(myScanner.nextLine());

you're making the input, that would usaully be a string, into a BigDecimal?

[s0meb0dy]

cool thanks but let me try it...

[Fubarable]

so, trying to understand your post, when you put
you're making the input, that would usaully be a string, into a BigDecimal?

It is a String but is passed into the BigDecimal constructor to be made into a BigDecimal. I could just as easily have done:

      Scanner myScanner = new Scanner(System.in);

      System.out.print("Enter a Number: ");
      String reply = myScanner.nextLine();
      BigDecimal myBigDecimal = new BigDecimal(reply);

[s0meb0dy]

so i should rewrite my program with BigDecimals instead of the previous?

[s0meb0dy]

how do i mark the post as solved. Thanks very much i think i understand the website you gave me more now. thanks

[Fubarable]

how do i mark the post as solved. Thanks very much i think i understand the website you gave me more now. thanks

Great because knowledge of how to use the API will give you more help in the future than I or even Norm can. It is probably the single most important skill you'll need to get you from a beginner Java programmer to an intermediate.

And to mark the post as solved, please look at the Thread Tools at the top.

Much luck!