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类型不匹配:无法从double转换为int java

[英]type mismatch: can't convert from double to int java

public static void main(String[] args) {
try{
    BufferedReader br=new BufferedReader(new FileReader("file.txt"));

    String[] pole=br.readLine().split(" ");
    double L=Double.parseDouble(pole[0]);
    double N=Double.parseDouble(pole[1]);
    String[] weight=new String[N];
    double[] scale=new double[N];
    double[] place=new double[N];
    for(int i=0; i<N; i++){
        weight[i]=br.readLine();
        String[] variable=weight[i].split(" ");
        double variable1=Double.parseDouble(variable[0]);
        double variable2=Double.parseDouble(variable[1]);
        scale[i]=variable2;
        place[i]=variable1*variable2;               
    }

I have this java code. 我有这个java代码。 I Want to get the number from the file and convert them into double, but it gives me that error: type mismatch: can't convert from double to int. 我想从文件中获取数字并将其转换为double,但这给了我一个错误:类型不匹配:无法从double转换为int。 How can I fix this? 我怎样才能解决这个问题?

Since N is double You need a type case there 由于N是double您需要一个类型大小写

String[] weight=new String[(int)N];

The reason is double is a floating point type and you cannot create an array of length 1.5 :) 原因是double是浮点类型,因此无法创建length 1.5的数组:)

Try with this 试试这个

public class Tuple {

    public static void main(String[] args) {
        try{
            BufferedReader br=new BufferedReader(new FileReader("UserController.txt"));

            String[] pole=br.readLine().split(" ");
            double L=Double.parseDouble(pole[0]);
            double N=Double.parseDouble(pole[1]);
            System.out.println("L is "+L);
            String[] weight=new String[(int) N];
            double[] scale=new double[(int) N];
            double[] place=new double[(int) N];
            for(int i=0; i<N; i++){
                weight[i]=br.readLine();
                String[] variable=weight[i].split(" ");
                double variable1=Double.parseDouble(variable[0]);
                double variable2=Double.parseDouble(variable[1]);
                scale[i]=variable2;
                place[i]=variable1*variable2;               
            }
        }
            catch(Exception e) {
                e.printStackTrace();
            }
    }
 }

N is a double but you're attempting to iterate over it. N是一个双精度型,但您正在尝试对其进行迭代。 You must type cast it. 您必须输入强制转换。

your problem is here.. 你的问题在这里..

double L=Double.parseDouble(pole[0]);
double N=Double.parseDouble(pole[1]);

change to 改成

 int L=Integer.parseInt(pole[0]);
 int N=Integer.parseInt(pole[1]);

because int only accept is array index.. 因为int只接受数组索引。

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