This question already has answers here:
How to round a number to n decimal places in Java
(39 answers)
Closed 2 years ago.
double1 = .05100000000003;
double2 = .05295;
How do I round a decimal to three places? Respectively, I'd like the output to do this 0.051 and 0.053.
I tried Math.round(double1); but I got back 0.0.
Any ideas would be greatly appreciated thanks.
Try the following code in Java. The number of zeros indicates how many decimal places you would like to round to. (In this case there are 3 zeros).
(double)Math.round(value * 1000d) / 1000d
EDIT: same answer is provided in this previous StackOverflow Post
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This question already has answers here:
How to round a number to n decimal places in Java
(39 answers)
Closed last year.
Like it comes : 692589
i want the value similar : 69.23
I want to know more than one process to perform this task in java
you can use DecimalFormat("0.00") to ensure the number is round to 2 decimal places. and maybe this can help you.
https://mkyong.com/java/java-display-double-in-2-decimal-points/#:~:text=format(%E2%80%9C%25.,double%20to%202%20decimal%20places.
This question already has an answer here:
Division between integers in Java
(1 answer)
Closed 3 years ago.
I've been struggling with Math.asin() for a while.
System.out.println(Math.toDegrees(Math.asin(1 / 2)));
This very simple line of code pretty much sums up my desperation: The result should be 30°, however, I only get 0.0 as a result. Its not just these numbers, no matter which numbers I use, the result is 0.0.
My question is, is this a known bug of Java, or am I missing something?
Bonus Information:
I need asin() to calculate the angle between the centerpoints of two objects in my game.
You’re doing integer division, please add a decimal point in the end of each number like this:
System.out.println(Math.toDegrees(Math.asin(1.0/2.0)))
This question already has answers here:
How to round a number to n decimal places in Java
(39 answers)
Closed 3 years ago.
I am using Math.round(). This is the sample code:
double value = 0.14499999970197677;
value = Math.round( value* 100.0) / 100.0;
My expectation is it should return 0.15 but it is returning 0.14
Also, if the value is 0.13499999970197677, then it is returning 0.13, why not 0.14
I have already gone through the link round up to 2 decimal places in java?
Please tell me clearly that why this is happening with both the numbers?
In Java, Math.round rounds up/down to closest long value (in mathematics terms, closest whole number).
14.49 will be rounded to 14 (because it is treated as 14.4). It won't take the .09 into account.
This question already has answers here:
Is floating point math broken?
(31 answers)
Closed 4 years ago.
I have odd problem in my java code. Why does every number lower than 0.4f multiplied by 0.0025f gives me wrong results.
Correct result:
0.4f * 0.0025f = 0.001f
Wrong results:
0.399999f * 0.0025f = 9.999975E-4
instead of 0.000999998f
0.33333f * 0.0025f = 8.33325E-4
instead of 0.000833325f
0.11111f * 0.0025f = 2.77775E-4
instead of 0.000277775f
How are you printing your results. You should maybe look at that. It sounds like you don't understand exponential notation.
9.999975E-4 == 0.000999975
The E-4 just means shift the decimal 4 places to the right.
Furthermore, you're doing your own math wrong. You have a number ending in a 9 multiplied by a number ending in 5, which means the answer is going to end in a 5 (9 x 5 is 45, after all). So it's NOT going to be 0.000999998. You got that answer from something that rounded it, perhaps a calculator that won't show it all the way out.
You don't have a math problem. You have a display problem, and not really. It's that you don't understand the display.
Perhaps look up the printf methods and use a format string with lots of room for data after the decimal.
This question already has answers here:
How to round a number to n decimal places in Java
(39 answers)
Closed 6 years ago.
I was looking for a simple way to round a double value to 10 digits but I didn't found even one way that look good to me, everything was too complicated.
I hope someone could help me, for example: the value 0.83426945721236485 will become 0.8342694572
Thank you in advance.
Simple.
DecimalFormat df = new DecimalFormat("0.0000000000");
System.out.println(df.format(0.83426945721236485));
Take a look at the documentation:
https://docs.oracle.com/javase/8/docs/api/java/text/DecimalFormat.html
Decimal places are not meaningful internally for double, because it is a binary floating point.
You can, of course, choose to display it in any format supported by DecimalFormat, as suggested in a prior answer.
If you want a ten decimal place internal representation, you should be using BigDecimal with scale factor 10.