C++ C++；：如何在不获取SIGSEV错误的情况下访问结构

我正在编写一个小的实用程序类，它将纬度和经度转换为UTM本地系统。对于我正在使用的这个任务。我创建了一些

struct

来帮助我管理大部分数据，但是如果我以特定的方式传递数据，就会出现问题。如果我清楚地重新声明这些值，它确实有效。请参见下面的示例：

zoneconverter.h

#ifndef ZONE_CONVERTER_H
#define ZONE_CONVERTER_H

#include <string>
#include <math.h>
#include <cmath>
#include <ctgmath>
#include <stdlib.h>
#include <stdio.h>
#include <stdexcept>

#define PI 3.14159265358979323846  /* pi */
#define SMaxA 6378137.0            /* semi major axis */
#define SMinA 6356752.314245       /* sdmi minor axis */
#define grid_size 100000.0         /* 100 km grid*/

struct Deg2Rad {
  double D2R = PI/180.0;
};

struct Rad2Deg {
    double R2D = PI*180.0;
};

// definition of the World Geodetic System 84
struct WGS84_DATA
{
    double semi_major_axis_a      = 6378137.0;            // by definition
    double semi_minor_axis_b      = 6356752.314245;       // by definition
    const double flattening             = (SMaxA-SMinA)/SMaxA;  // by definition
    const double first_eccentricity     = 0.081891909;          // by calculation
    double second_eccentricity    = 0.0820944377;         // by calculation
    double angular_velocity_earth = 72.92115e-6;          // rad/s
    double gravitational_constant = 3986004.418e8;        // by definition
};

struct UTM_DATA
{
    double point_scale_factor  = 0.9996;                  // by convention
    double equatorial_radius   = 6378137.0;               // meters also semi_major_axis_a
    double inverse_flattening  = 1/((SMaxA-SMinA)/SMaxA); // by convention
    double northen_emisphere   = 0.0;                     // meter
    double southern_hemisphere = 10000000.0;              // meter
    double false_esting        = 500000.0;                // meter by convention
    double first_eccentricity_power2 = 0.081891909*0.081891909;
    double first_eccentricity_power4 = 0.081891909*0.081891909*0.081891909*0.081891909;
    double first_eccentricity_power6 = 0.081891909*0.081891909*0.081891909*0.081891909*0.081891909*0.081891909;
};

enum UTMidentifierLeter {
    X, W, V, U, T, S, R, Q, P, N,
    M, L, K, J, H, G, F, E, D, C, Z
};

struct UTM_LETTER_ZONE { UTMidentifierLeter utmLetterZone; };
enum UTMIdentifierZone { NORWAY, SVALBARD };
struct UTM_ZONE { UTMIdentifierZone utmZone; };

class ZONE_converter
{
public:
  ZONE_converter();
  WGS84_DATA wgs84_data;
  UTM_DATA utm_data;
  Deg2Rad degreeToRad_reader;
  Rad2Deg radToDeg_reader;
  void UTM(double lat, double lon, double eastingUtmzone, double northingUtmzone);
  char adjustForNorway(double lat);
  char adjustForSvalbard(double lat, double lon);
  char allOtherZones(double lat);

private:
  UTM_LETTER_ZONE letter;
  UTM_ZONE zone;
  double latitude;
  double longitude;
  int current_zone;
};

#endif // ZONE_CONVERTER_H

---

有人能解释一下这个问题吗？

一个问题是，您在这里使用的是未初始化的变量：

double eastingUtmzone;  // uninitialized
double northingUtmzone; // uninitialized
convert.UTM(lat, lon, eastingUtmzone, northingUtmzone);
std::cout<< lat << lon<< northingUtmzone<< eastingUtmzone<< std::endl;

double eastingUtmzone；//未初始化
双北区；//未初始化
转换为UTM（纬度、经度、东印古特区、北印古特区）；
std：：cout
（SMaxA SMinA）/SMaxA
——这些是变量还是常量？你也检查过你所有的值，以确保它们不是无效的double、nan等吗？@PaulMcKenzie，感谢你阅读这个问题，我在标题中定义了它们，请参阅更新的codeFYI——请注意，你发布的大部分内容可能是
常量double
，而不仅仅是
double
。类似于
ZONE\u converter:：UTM
的内容都是常量数据。
SIGSEGV
表示内存错误，很可能是试图取消对空指针或无效指针的引用。您需要使用调试器来帮助您找到代码中崩溃发生的位置，并在该位置检查所有相关变量的值。@Emanuele您的
Zone_converter
构造函数无法初始化您的成员变量。那是一面红旗。请发一封信。
#include <iostream>
#include "zone_converter.h"
using namespace std;

int main()
{
    ZONE_converter convert;
    double lat = 26.281742;
    double lon = 92.142683;

    double eastingUtmzone;
    double northingUtmzone;
    convert.UTM(lat, lon, eastingUtmzone, northingUtmzone);
    std::cout<< lat << lon<< northingUtmzone<< eastingUtmzone<< std::endl;

    return 0;
}

void ZONE_converter::UTM(double lat, double lon, double eastingUtmzone, double northingUtmzone)
{    
    double m0_a11 = (std::pow(wgs84_data.first_eccentricity, 2)/4);
    double m0_a12 = (std::pow(wgs84_data.first_eccentricity, 4)/64);
    double m0_a13 = (std::pow(wgs84_data.first_eccentricity, 6))/256;

    double m0 = 1 - m0_a11 - 3*m0_a12 - 5*m0_a13;

    // ... additional operation
}

double eastingUtmzone;  // uninitialized
double northingUtmzone; // uninitialized
convert.UTM(lat, lon, eastingUtmzone, northingUtmzone);
std::cout<< lat << lon<< northingUtmzone<< eastingUtmzone<< std::endl;