Java:循环计算总计
时间: 2023-05-31 18:08:04 浏览: 62
这是一个编程问题,我可以回答。在 Java 中,可以通过 for 循环来计算总计。示例代码如下:
int[] arr = {1, 2, 3, 4, 5};
int sum = 0;
for (int i = 0; i < arr.length; i++) {
sum += arr[i];
}
System.out.println(sum);
输出结果为 15,即数组中所有元素的和。
相关问题
excel表格总计java
Excel表格总计是指在Excel中计算一列或多列数据的总和。在Java后台生成Excel表格时,你可以使用jxl库中的相关方法来实现这个功能。下面是一个示例代码,展示了如何使用jxl计算Excel表格中某列数据的总和:
```
// 导入jxl库
import jxl.*;
import jxl.write.*;
import java.io.*;
public class ExcelGenerator {
public static void main(String[] args) {
try {
// 创建Excel工作簿
WritableWorkbook workbook = Workbook.createWorkbook(new File("output.xls"));
// 创建Excel工作表
WritableSheet sheet = workbook.createSheet("Sheet1", 0);
// 假设数据存在第一列的A1到A10单元格中
double total = 0;
for (int row = 0; row < 10; row++) {
// 获取单元格的值并进行累加
Cell cell = sheet.getCell(0, row);
double value = Double.parseDouble(cell.getContents());
total += value;
}
// 在Excel中显示总计
Label label = new Label(0, 10, "总计:" + total);
sheet.addCell(label);
// 保存并关闭Excel文件
workbook.write();
workbook.close();
} catch (Exception e) {
e.printStackTrace();
}
}
}
```
java复数类总计
以下是一个简单的 Java 复数类:
```
public class Complex {
private double real;
private double imag;
public Complex(double real, double imag) {
this.real = real;
this.imag = imag;
}
public double getReal() {
return real;
}
public double getImag() {
return imag;
}
public Complex add(Complex other) {
double newReal = this.real + other.real;
double newImag = this.imag + other.imag;
return new Complex(newReal, newImag);
}
public Complex subtract(Complex other) {
double newReal = this.real - other.real;
double newImag = this.imag - other.imag;
return new Complex(newReal, newImag);
}
public Complex multiply(Complex other) {
double newReal = this.real * other.real - this.imag * other.imag;
double newImag = this.real * other.imag + this.imag * other.real;
return new Complex(newReal, newImag);
}
public Complex divide(Complex other) {
double denominator = other.real * other.real + other.imag * other.imag;
double newReal = (this.real * other.real + this.imag * other.imag) / denominator;
double newImag = (this.imag * other.real - this.real * other.imag) / denominator;
return new Complex(newReal, newImag);
}
public String toString() {
return real + " + " + imag + "i";
}
}
```
这个类包含了基本的复数运算:加、减、乘、除。可以通过创建新的 `Complex` 对象来表示结果。同时,这个类也包含了获取实部和虚部的方法,以及重写了 `toString()` 方法。