应输入标识符，如下图报错,都是什么原因，应该怎么改？

Question

#ifndef _POINT_H
#define _POINT_H
class Point {//Piont类的定义
public:
    Point(float x = 0,float y = 0) : x(x), y(y){}
    float getX() const { return x; }
    float getY() const { return y; }
private:
    float x, y;
};
#endif





#include <iostream>
#include "Point.h"
#include <cmath>
using namespace std;
    //直线线性拟合，points为各点,nPiont为点数
float lineFit(const Point Points[], int nPoint);
    float lineFit(const Point Points[], int nPoint) {
        float avgX = 0, avgY = 0;
        float 1xx = 0, 1yy = 0, 1xy = 0;
        for (int i = 0; i < nPoint; i++)
        {
            avgX += points[i].getX() / nPoint;
            avgY += points[i].getY() / nPoint;
        }
        for (int i = 0; i < nPoint; i++)
        {
            1xx += (points[i].getX() - avgX) * (points[i].getX - avgX);
            1yy += (points[i].getY() - avgY) * (points[i].getY - avgY);
            1xy += (points[i].getX() - avgX) * (points[i].getY - avgY);
        }
        cout << "This line can be fitted by y=ax+b." << endl;
        cout << "a=" << 1xy / 1xx << " ";
        cout << "b=" << avgY - 1xy * avgX / 1xx << endl;
        return static_cast<float>(1xy / sqrt(1xx * 1yy));
    }
    int main()
    {
        Point p[10] = { Point(6,10),Point(14,20), Point(26,30), Point(33,40), Point(46,50), Point(56,60), Point(67,70), Point(75,80), Point(84,90), Point(100,100), };
        float r = lineFit(p, 10);
        cout << "Line coefficient r=" << r << endl;
        return 0;
    }

Answer 1

1、Points写成了points。
2、还有变量不能以数字开头命名，你写成了1xx
float 1xx = 0, 1yy = 0, 1xy = 0;
3、Points[i].getX写错了，应该写成Points[i].getX()

#include <iostream>
#include <cmath>
using namespace std;

class Point {//Piont类的定义
public:
    Point(float x = 0, float y = 0) : x(x), y(y) {}
    float getX() const { return x; }
    float getY() const { return y; }
private:
    float x, y;
};

//直线线性拟合，points为各点,nPiont为点数
float lineFit(const Point Points[], int nPoint);
float lineFit(const Point Points[], int nPoint) 
{
    float avgX = 0, avgY = 0;
    float xx = 0, yy = 0, xy = 0;
    for (int i = 0; i < nPoint; i++)
    {
        avgX += Points[i].getX() / nPoint;
        avgY += Points[i].getY() / nPoint;
    }
    for (int i = 0; i < nPoint; i++)
    {
        xx += (Points[i].getX() - avgX) * (Points[i].getX() - avgX);
        yy += (Points[i].getY() - avgY) * (Points[i].getY() - avgY);
        xy += (Points[i].getX() - avgX) * (Points[i].getY() - avgY);
    }
    cout << "This line can be fitted by y=ax+b." << endl;
    cout << "a=" << xy / xx << " ";
    cout << "b=" << avgY - xy * avgX / xx << endl;
    return static_cast<float>(xy / sqrt(xx * yy));
}
int main()
{
    Point p[10] = { Point(6,10),Point(14,20), Point(26,30), Point(33,40), Point(46,50), Point(56,60), Point(67,70), Point(75,80), Point(84,90), Point(100,100), };
    float r = lineFit(p, 10);
    cout << "Line coefficient r=" << r << endl;
    return 0;
}