为什么该程序告诉我传递了无效的参数?

时间:2019-02-03 23:01:42

标签: c++ parameter-passing 2d-vector

老实说,到目前为止,我什至不知道我要做什么。但是,直到我使该功能正常工作,我才能走得更远,并且每次都会抛出该异常,这是怎么回事?例外是“ CS 330 19S,P1,Calvert,程序1.exe中0x0F61CAB6(ucrtbased.dll)的未处理的例外:将无效参数传递给认为无效参数致命的函数”

#include<iostream>
#include<vector>
#include <fstream>
using namespace std;

struct Kinematic {
    vector<vector<float>> position;
    float orientation;
    vector<vector<float>> velocity;
    float rotation;
};

struct StreeringOutput {
    vector<vector<float>> linear;
    float angular;
};

void update(StreeringOutput steering, float time, Kinematic k) 
{
    for (int i = 0; i < 100; i++) 
    {
        for (int j = 0; j < 100; j++) 
        {
            k.position[i][j] += k.velocity[i][j] * time + 
                           0.5*steering.linear[i][j] * time*time;
                           //the above command is where it throws the exception
            k.velocity[i][j] += steering.linear[i][j] * time;
        }
    }
    k.orientation += k.rotation*time + 0.5*steering.angular*time*time;
    k.rotation = steering.angular*time;

}


int main()
{
    int test;
    Kinematic kin;
    StreeringOutput steering;
    float time = 0.0;

    ofstream outfile;
    outfile.open("Output.txt");

    for (int i = 0; i < 100; i++)
    {
        update(steering, time, kin);
        time += 0.5;
    }
    cin >> test;
    return 0;
}

1 个答案:

答案 0 :(得分:2)

程序启动时,您将创建对象:

Kinematic kin;
StreeringOutput steering;

这称为默认初始化,即所有成员都被初始化为默认值。对于vector,它是空状态。

但是update做这些事情:

// i and j can be as large as 99
k.position[i][j]
k.velocity[i][j]
steering.linear[i][j]

但是position等是空的! vector无法自动增长以适应您的需求。您正在索引越界,这是未定义的行为。

您应该正确初始化向量,以确保实际上有100个元素:

Kinematic kin;
kin.position.assign(100, vector<float>(100));
// same for others