double

问题 I want to let users edit a field with double data in Grails view. I want to allow Double.NaN (to void values). There is a special char looking like a diamond with a question mark in it (in HTML) that acts like NaN, but - well - the users wont find that on their keys. In Java it works with Double.valueOf("NaN") . But typing NaN in the input field will throw a IllegalArgumentException saying "NaN" is an Unparseable Number. What method is callled for conversion? Whats the key to let it

问题 I have this simple piece of code and I am wondering how to convert it to German format (#.###,##) ? // displays #.## <DataGridTextColumn Header="Sum Value" Binding="{Binding SumValue}"/> 回答1: In this case try several options: A. Global setting language culture for the entire application, it can solve some problems related to the current language culture. Add Startup event for App.xaml , which establishes the necessary language culture. It affects the display of the date, double values​​, sums

问题 This question already has answers here : Double decimal formatting in Java (14 answers) Closed 5 years ago . I am to convert a double value to a String. double d=12345678.999; String str = String.valueOf(d); or, just plain String str = ""+d; Does it, however in the exponent form-- returning the String value: 1.2345678999E7 I need the value as is in the String: 12345678.999 Is there a way to do this? I can parse the string for the value of exponent-- the portion after 'E' and go from there,

问题 I input 179.9 in an EditText . When I retrieve it, the value is different if it's stored as a float . final EditText valueInput = mEntryDialogView.getValueInput(); final CharSequence input = valueInput.getText(); final String inputAsString = input.toString().trim(); final float asFloat = Float.valueOf(inputAsString); //179.899994 final double asDouble = Double.valueOf(inputAsString); //179.9 Something fishy is going on here, could anyone explain to me why the float value is not correct ? Even

问题 i want to floor a double by its decimal place with variable decimal length (in iphone sdk). here some examples to show you what i mean NSLog(@"%f",[self floorMyNumber:34.52462 toPlace:2); // should return 34.52 NSLog(@"%f",[self floorMyNumber:34.52662 toPlace:2); // should return 34.52 NSLog(@"%f",[self floorMyNumber:34.52432 toPlace:3); // should return 34.524 NSLog(@"%f",[self floorMyNumber:34.52462 toPlace:3); // should return 34.524 NSLog(@"%f",[self floorMyNumber:34.12462 toPlace:0); //

问题 i want to floor a double by its decimal place with variable decimal length (in iphone sdk). here some examples to show you what i mean NSLog(@"%f",[self floorMyNumber:34.52462 toPlace:2); // should return 34.52 NSLog(@"%f",[self floorMyNumber:34.52662 toPlace:2); // should return 34.52 NSLog(@"%f",[self floorMyNumber:34.52432 toPlace:3); // should return 34.524 NSLog(@"%f",[self floorMyNumber:34.52462 toPlace:3); // should return 34.524 NSLog(@"%f",[self floorMyNumber:34.12462 toPlace:0); //

问题 I have the following code: double dtemp = (some value) printf("\n***Hand washing: cost per kg/item: %.2f, cost: %.2f.\n", 5, dtemp); It prints out: ***Hand washing: cost per kg/item: 0.00, cost: 0.00. And when I change the constant 5 into a double variable holding 5, it prints (according to the input): ***Hand washing: cost per kg/item: 5.00, cost: 20.00. Why would the constant 5 affect the evaluation of the dtemp? I'm using gcc 4.6.2 (MinGW) and tested it also in TCC. 回答1: My compiler's (gcc

问题 I have an NSArray in which I would like to store double values. I defined it as follow NSMutableArray *setOfDoubles; I add the elements as follow NSNumber *num; num = [NSNumber numberWithDouble:someDouble]; [setOfDoubles addObject:num]; And I read the element as follow num = [setOfDoubles lastObject]; [setOfDoubles removeLastObject]; doubleValueToUse = [num doubleValue]; My problem is sometimes (Not always), for example when num (as an object) is 5.1, doubleValueToUse (as a double value) is 5

问题 When performing conversion from byte to double by mathematical operations I've got expected result. Performing the same mathematical operations to reverse the changes in value, results in correct value as long as I keep double type. But when at the end I converts double result back to byte value the conversion results is incorrect by 1. This is the case only for some byte values. Exact process: byte b = 82; Console.WriteLine(b); // initial byte value double d = (b / 100.0) + 2.00; Console

问题 When performing conversion from byte to double by mathematical operations I've got expected result. Performing the same mathematical operations to reverse the changes in value, results in correct value as long as I keep double type. But when at the end I converts double result back to byte value the conversion results is incorrect by 1. This is the case only for some byte values. Exact process: byte b = 82; Console.WriteLine(b); // initial byte value double d = (b / 100.0) + 2.00; Console