intdecimalPlaces=doubleStr.length()-dotIndex-1; 1. 现在,我们已经完成了判断double类型的变量有几位小数的过程。接下来,让我们用代码示例来演示一下。 publicclassDecimalPlaces{publicstaticvoidmain(String[]args){doublenumber1=3.14;doublenumber2=2.71828;intdecimalPlaces1=getDecimalPlaces(number1);intdecimalP...
importjava.text.DecimalFormat;publicclassDecimalPlacesExample{publicstaticvoidmain(String[]args){doublenumber=3.14159265358979323846;DecimalFormatdf=newDecimalFormat("#.###");StringformattedNumber=df.format(number);intdecimalPlaces=formattedNumber.length()-formattedNumber.indexOf('.')-1;System.out.println("N...
public class DecimalOutputExample { public static void main(String[] args) { double decimalNumber = 123.456789; // 默认格式输出(通常保留 6 位小数) System.out.printf("Default format: %f%n", decimalNumber); // 保留两位小数 System.out.printf("Two decimal places: %.2f%n", decimalNumber); ...
Round a double to 2 decimal places [duplicate] Solution 1: This tool performs rounding on a double value to a specific number of decimal places rather than truncating it. For example: round(200.3456, 2); // returns 200.35 Original version; watch out with this public static double round(doub...
To rounddoubles tondecimal places, we can write ahelper method: private static double round(double value, int places) { if (places < 0) throw new IllegalArgumentException(); BigDecimal bd = new BigDecimal(Double.toString(value)); bd = bd.setScale(places, RoundingMode.HALF_UP); ...
doublenum=3.14159;Stringresult=String.format ("%.1f", num);// result = "3.1" 复制 使用DecimalFormat 类,它可以按照指定的模式来格式化数值,比如 “#.#” 表示保留一位小数。例如: doublenum=3.14159;DecimalFormatdf=newDecimalFormat("#.#");Stringresult=df.format (num);// result = "3.1" ...
We specify a new pattern withapplyPattern. This pattern adds zeros to decimal places, if they are empty. Grouping digits The,format character is used for grouping of digits. Main.java import java.text.DecimalFormat; void main() { double n = 2_125_405.30; ...
{ public static void main(String[] args) { double number =12.34567; int decimalPlaces = 2; ...
We can create a supporting function to convert double values into n decimal places instead of rounding them. private static double round(double value, int places) { if (places < 0) throw new IllegalArgumentException(); BigDecimal bd = new BigDecimal(Double.toString(value)); ...
数据类型:限制变量存储的数据类型,例如int表示整数,double表示小数 变量名:表示存储空间的名字,根据变量名找到存储空间 *///声明一个整数类型的变量,变量名是age,变量的类型是整数类型intage;/* 变量赋值的语法格式 变量名 = 变量值; 等号(=):赋值运算符,用于将=右边的值赋值给左边的变量 ...