dbgheap.c引發訪問沖突異常

Question

我開發了下面的代碼，效果很好：

#include "header.h"

int test_DGGEV_11_14a(){
    const int n=3;
    double a[n][n]={1,1,1,2,3,4,3,5,2};
    double b[n][n]={-10,-3,12,14,14,12,16,16,18};
    //double a[n][n]={1,7,3,2,9,12,5,22,7};
    //double b[n][n]={1,7,3,2,9,12,5,22,7};

    /*const int n=2;
    double a[n][n]={1e-16,0,0,1e-15};
    double b[n][n]={1e-16,0,0,1e-15};*/

    lapack_int info;
    double alphar[n]={0.0};
    double alphai[n]={0.0};
    double beta[n]={0.0};
    double vl[n][n]={0.0};
    double vr[n][n]={0.0};

    info=LAPACKE_dggev(LAPACK_ROW_MAJOR,'V','V',n,*a,n,*b,n,alphar,alphai,beta,*vl,n,*vr,n);

    std::cout<<"right eigen vector (what we want):\n";
    for(int i=int(0);i<n;i++){
        for(int j=int(0);j<n;j++){
            printf("%1f ",vr[i][j]);
        }
        printf("\n");
    }
    std::cout<<"left eigen vector:\n";
    for(int i=int(0);i<n;i++){
        for(int j=int(0);j<n;j++){
            printf("%1f ",vl[i][j]);
        }
        printf("\n");
    }
    std::cout<<"eigen values:\n";
    for(int i=int(0);i<n;i++){
        if(beta[i]>DBL_MIN || beta[i]<-DBL_MIN){
            printf("%1f ",alphar[i]/beta[i]);
            printf("\n");
        }else{
            printf("%1f ","beta is zero");
            printf("\n");
        }
    }
    return info;
}

我修改了上面的正確代碼，以對大型矩陣使用LAPACKE DGGEV例程，修改后的代碼如下所示：

#include "header.h"

int test_DGGEV_11_17a(){
    const int r=342;
    const int c=342;
    double**a=NULL;//stiffness
    a=new double *[r];
    for(int i=int(0);i<r;i++)
        a[i]=new double[c];
    readFile("Input_Files/OUTPUT_sub_2_stiffness.txt",a,r,c);
    writeFile("Output_Files/K.txt",a,r,c);//to check if readFile was OK

    double**b=NULL;//mass
    b=new double*[r];
    for(int i=int(0);i<r;i++)
        b[i]=new double[c];
    readFile("Input_Files/OUTPUT_sub_2_mass.txt",b,r,c);
    writeFile("Output_Files/M.txt",b,r,c);//to check if readFile was OK

    const int n=r;//r=c=n
    lapack_int info=110;
    double alphar[n]={0.0};
    double alphai[n]={0.0};
    double beta[n]={0.0};
    //double vl[n][n]={0.0};//generates stack overflow
    double**vl=NULL;
    vl=new double*[r];
    for(int i=int(0);i<r;i++)
        vl[i]=new double[c];
    for(int i=int(0);i<r;i++)
        for(int j=int(0);j<c;j++)
            vl[i][j]=0.0;
    //double vr[n][n]={0.0};//generates stack overflow
    double**vr=NULL;
    vr=new double*[r];
    for(int i=int(0);i<r;i++)
        vr[i]=new double[c];
    for(int i=int(0);i<r;i++)
        for(int j=int(0);j<c;j++)
            vr[i][j]=0.0;

    info=LAPACKE_dggev(LAPACK_ROW_MAJOR,'V','V',n,*a,n,*b,n,alphar,alphai,beta,*vl,n,*vr,n);

    return info;
}

在上面修改的代碼中（對於大型矩陣），我必須從堆中分配內存，因為否則，堆棧將溢出。 問題是，當我通過new從堆中分配內存時，出現以下與堆相關的異常，該異常發生在dbgheap.c （調試CRT堆功能）內部：

有人知道為什么會發生這種異常嗎？ 也許這與LAPACKE DLL使用不同的堆進行分配這一事實有關...我不知道。

---

編輯：

堆棧跟蹤是這樣的：

---

編輯：

最終通過用1D數組替換所有2D數組解決了該問題。 以下代碼是正確的代碼，可以正常工作。 有關此解決方案的詳細信息，請參見“ Ilya Kobelevskiy”的答案。

int test_DGGEV_11_18a(){
    const int r=342;
    const int c=342;
    double*a=NULL;//stiffness
    a=new double [r*c];
    for(int i=int(0);i<r*c;i++)
            a[i]=0.0;
    readFile_1Darray("Input_Files/OUTPUT_sub_2_stiffness.txt",a,r,c);
    writeFile_1Darray("Output_Files/K.txt",a,r,c);//to check if readFile was OK

    double*b=NULL;//mass
    b=new double[r*c];
    for(int i=int(0);i<r*c;i++)
            b[i]=0.0;
    readFile_1Darray("Input_Files/OUTPUT_sub_2_mass.txt",b,r,c);
    writeFile_1Darray("Output_Files/M.txt",b,r,c);//to check if readFile was OK

    const int n=r;//r=c=n
    lapack_int info=110;

    //double alphar[n]={0.0};
    double*alphar=NULL;
    alphar=new double[n];
    for(int i=int(0);i<n;i++)
        alphar[i]=0.0;
    //double alphai[n]={0.0};
    double*alphai=NULL;
    alphai=new double[n];
    for(int i=int(0);i<n;i++)
        alphai[i]=0.0;
    //double beta[n]={0.0};
    double*beta=NULL;
    beta=new double[n];
    for(int i=int(0);i++;)
        beta[i]=0.0;
    //double vl[n][n]={0.0};//generates stack overflow
    double*vl=NULL;
    vl=new double[r*c];
    for(int i=int(0);i<r*c;i++)
            vl[i]=0.0;
    //double vr[n][n]={0.0};//generates stack overflow
    double*vr=NULL;
    vr=new double[r*c];
    for(int i=int(0);i<r*c;i++)
            vr[i]=0.0;

    info=LAPACKE_dggev(LAPACK_ROW_MAJOR,'V','V',n,a,n,b,n,alphar,alphai,beta,vl,n,vr,n);
    std::cout<<"info returned by LAPACKE_dggev:\t"<<info<<'\n';

    double*eigValueReal=NULL;
    eigValueReal=new double[n];
    for(int i=int(0);i<n;i++)
        eigValueReal[i]=0.0;
    for(int i=int(0);i<n;i++)
        eigValueReal[i]=alphar[i]/beta[i];

    write1Darray("Output_Files/eigValueReal_LAPACKE_DGGEV.txt",eigValueReal,n);
    write1Darray("Output_Files/beta.txt",beta,n);
    writeFile_1Darray("Output_Files/eigVectorRight_LAPACKE_DGGEV.txt",vr,r,c);

    delete[] a;
    delete[] b;
    delete[] alphar;
    delete[] alphai;
    delete[] beta;
    delete[] vl;
    delete[] vr;
    delete[] eigValueReal;

    return info;
}

Answer 1

根據文檔， LAPACKE_dggev希望將double *作為輸入，因此所有矩陣都需要存儲為線性數組。

代替

double**a=NULL;//stiffness
a=new double *[r];
for(int i=int(0);i<r;i++)
    a[i]=new double[c];

你應該用

double*a=new double[c*r];//stiffness

所有矩陣的變化都相似。 矩陣元素可以作為a [i，j]的a [i * c + j]訪問。 現在，您的代碼可能還有其他問題，但這是一個顯而易見的問題，可能會導致您看到錯誤。