Question

我不知道为什么错误会在标题中提到。数据都是数字，并且在没有指针的情况下测试时函数会毫无问题地读取数据。

注意：我不需要使用＆＃39; malloc＆＃39;或任何其他的。我试图弄清楚结构的内容。

#include<stdio.h>
#include<stdlib.h>
#include<math.h>
#include<limits.h>
#define MAX_POINTS 100
#define MAX_POLYGONS 100

typedef struct{
    int polyid;
    int npoints;
    double x[MAX_POINTS];
    //Stage1
    double y[MAX_POINTS];
    double perimeter;
    double eccentricity;
    double area;
} Polygon;

typedef struct {
    Polygon npolygon[MAX_POLYGONS];
}polygons;
//function prototypes
void process_file(polygons *Total_poly);
int largestvalue_index(double A[],int m);
int largest_poly_id(double A[],int m, int B[]);
double area(double x[MAX_POINTS],double y[MAX_POINTS],int n);
double perimeter(double x[MAX_POINTS],double y[MAX_POINTS],int n);
double eccentricity(double area,double perimeter);

int main(int argc, char *argv[]) {
    int i,j,k,l;

    polygons Total_poly;
    process_file(Total_poly);
    printf("Stage 1\n");
    printf("=====\n");  
    printf("First Polygon %d\n",Total_poly->npolygon[0]->polyid);
    printf("x_val       y_val\n");
    for(i=0;i<Total_poly->npolygon[0].npoints;i++){
    printf("%8.2f %8.2f\n",Total_poly->npolygon[0]->x[i],
        Total_poly->npolygon[0]->y[i]);
    }
    printf("area=%.2f\n",area(Total_poly->npolygon[0].x,
        Total_poly->npolygon[0]->y,Total_poly->npolygon[0]->npoints));
    printf("perimeter=%.2f\n",perimeter(Total_poly->npolygon[0]->x,
        Total_poly->npolygon[0]->y,Total_poly->npolygon[0]->npoints));
    printf("eccentricity=%.2f\n",Total_poly->npolygon[0]->eccentricity);


    //Stage2
    printf("Stage 2");
    printf("=======\n");
    for(l=1;l<=5;l++){
        printf("+-------");
    }
    printf("+\n");
    printf("|    id |  nval | perim |  area | eccen |\n");
    for(l=1;l<=5;l++){
        printf("+-------");
    }
    printf("+\n");
    for(k=0;k<count;k++){
    printf("| %5d | %5d |%6.2f |%6.2f |%6.2f |\n",
        Total_poly->npolygon[k]->polyid,Total_poly->npolygon[k]->npoints,
        Total_poly->npolygon[k]->perimeter,Total_poly->npolygon[k]->area,
        Total_poly->npolygon[k]->eccentricity);
    }
    for(l=1;l<=5;l++){
        printf("+-------");
    }
    //Stage3
    return 0;
}
void process_file(polygons *Total_poly){
    int count=0;
    int i;
    while(scanf("%d %d",&Total_poly.npolygon[count].npoints,
        &Total_poly.npolygon[count].polyid)=2){
    for(i=0;i<Total_poly.npolygon[count].npoints;i++){
        if( scanf("%lf %lf",&Total_poly.npolygon[count].x[i],
            &Total_poly.npolygon[count].y[i])=!2)
        {
            printf("Error");
            exit(EXIT_FAILURE);
        }else{
            scanf("%lf %lf",&Total_poly.npolygon[count].x[i],
            &Total_poly.npolygon[count].y[i]);
        }



    }

    count++;    
    }
}

double area(double x[MAX_POINTS],double y[MAX_POINTS],int n){
    int i,j;
    double area=0;
    j=n-1;
    for(i=0;i<n;i++){
        area+=(x[i]-x[j])*(y[i]+y[j]);
        j=i;
    }
return 0.5*fabs(area);
}

double perimeter(double x[MAX_POINTS],double y[MAX_POINTS],int n){
    int i,j;
    double length=0;
    j=n-1;
    for(i=0;i<n;i++){
        length+=fabs(sqrt((x[i]-x[j])*(x[i]-x[j])+(y[i]-y[j])*(y[i]-y[j])));
        j=i;
    }
    return length;
}

double eccentricity(double area,double perimeter){
    return perimeter*perimeter/area/(4*M_PI);
}

int largest_poly_id(double A[],int m, int B[]){
    int i,j;
    int poly_index=0,largest = A[0];
    for(i=1;i<m;i++){
        if(A[i]>largest){
            largest=A[i];
            poly_index=i;
        }   
    }
    j=B[poly_index];
    return j;
}

int largestvalue_index(double A[],int m){
    int i;
    int index=0,largest=A[0];
    for(i=1;i<m;i++){
        if (A[i]>largest){
            largest=A[i];
            index=i;
        }
    }
    return index;
}

Answer 1

您正在将结构传递给process_file函数。但是，它期望指向结构的指针。

更改此行：

process_file(Total_poly);

到此：

process_file(&Total_poly);

此外，您需要将->功能printf语句中的main运算符更改为.运算符。

预期的结构多边形*＆＃39;但争论是

1 个答案: