double

问题 How to convert decimal presentation of an ip address to 32bit integer value in java? I use InetAddress class and getLocalHost method to obtain an IP adress: public class getIp { public static void main(String[] args) { InetAddress ipaddress; try { ipaddress=InetAddress.getLocalHost(); System.out.println(ipaddress); } catch(UnknownHostException ex) { System.out.println(ex.toString()); } } } Than I should convert the result to 32bit integer value and than to string, how do I do that? Thanks!

问题 What can I do to fix this? Here's part of the beginning of the code: double fee; double tuition; double[] residence, total; Here's the part where it's wrong: total = tuition + fee; error: incompatible types: double cannot be converted to double[] What do I do to fix this? 回答1: What you've done here is declared 4 variables: fee and tuition are of type double , while residence and total are of type double[] -- i.e. an array of elements of type double . You're adding up tuition and fee , and

问题 I'm getting the hexadecimal values of range 0x0000 to 0x01c2 from BLE to my phone a as String . In order to plot it in a graph, I have to convert it into double , for which I've tried this method but sadly it couldn't help in my case. Here is the little modified code from the provided link: String receivedData = CommonSingleton.getInstance().mMipsData; // 0x009a long longHex = parseUnsignedHex(receivedData); double d = Double.longBitsToDouble(longHex); public static long parseUnsignedHex

问题 public static void main(String[] args) { Gson g = new GsonBuilder() .setPrettyPrinting() .enableComplexMapKeySerialization() .serializeSpecialFloatingPointValues() .setLongSerializationPolicy(LongSerializationPolicy.DEFAULT) .setPrettyPrinting() //.registerTypeAdapter(HashMap.class, new HashMapDeserializer()) .create(); HashMap<Object, Object> h = new HashMap<Object, Object>(); h.put("num1", 10); h.put("num2", 20); h.put("num3", 20.0); h.put("num4", "<>"); h.put("num5", "~!@#$%^&*()_+=-`,.<>?

问题 This is driving me crazy. I have been looking for the source of the issue for hours, but i am starting to suspect this is not an issue in my logic... Maybe i am wrong. Issue description I have a simple Entry . Its Text property is bound to a property with type double in a ViewModel . At the same time i subscribe to the Unfocused Event whose EventHandler simply sets the entry.Text property to "1.0" (actually i can reproduce the issue for x.y0, that is any decimal whose final digit is 0). If

问题 What is significant difference between following zero double variable declaration: 0.0 VS 0d double d1 = 0.0; double d2 = 0d; I understand that both these are better than just 0 ,because are more obvious for code reader. However 0.0 VS 0d difference is not clear for me. 回答1: There is no difference. Have a look at the Java Language Specification, section 3.10.2 DecimalFloatingPointLiteral: Digits . Digits opt ExponentPart opt FloatTypeSuffix opt . Digits ExponentPart opt FloatTypeSuffix opt

问题 This question already has answers here : Closed 7 years ago . Possible Duplicate: Generating random number in a range with Java double x = //Random number between -0.5 and 0.5 Possible Outputs: -0.23 0.01 0.26 -0.4 How do I generate a double between the range of (example) -0.5 and 0.5 ? 回答1: This should do it Math.random() - 0.5 Math.random will generate betweeen 0 and 1 . If you want between -0.5 and +0.5 then you can just -0.5 from this result. See the API docs One thing that this will not

问题 I'd like a function that looks like this: int GetDecimalPlaces(string format, IFormatProvider formatProvider = null); The inputs would be exactly the same as those which can be legally passed to methods responsible for formatting numbers, e.g., double.ToString , decimal.ToString . The output would be an int indicating the lowest number of decimal places required by the format string. So here are a couple of example inputs/outputs I would expect (let's just say leaving formatProvider as null

问题 To convert double to string without scientific notation, the suggested way is std::ostringstream strStream; strStream << std::fixed; strStream << value; std::string str = strStream.str(); as in Prevent scientific notation in ostream when using << with double & How do I convert a double into a string in C++? I want to convert double to string without any separator and Dot/Full-stop as the decimal point, i.e. ignoring locale. From description of ostringstream, std::fixed and showpoint, I couldn

问题 What's the best method to mask an input field to only allow float/double, without any jquery plugin. Acutally i'm doing it like this: $("#defaultvalue").bind("keypress", function(e) { if (e.which != 8 && e.which != 0 && (e.which < 48 || e.which > 57)) { return false; } }); but thats only for numbers thx 回答1: JavaScripts parseFloat() function returns NaN, when your input is not a number. For i18n you will probably have to replace the floating point separator (e.g. , with .) 回答2: parseFloat