Question

伙计们，我想从我的文件中读取文本，并将每个字符分配给数组的单个元素

__global__ void setup_cuRand(curandState * state, unsigned long seed)
{
    int id = threadIdx.x;
    curand_init(seed, id, 0, &state[id]);
}

__global__ void poblar(int * adn, curandState * state){

    curandState localState = state[threadIdx.x];
    int random = curand(&localState);
    adn[threadIdx.x] = random;
    // It doesn't mind if i use the following instruction, the result is a lot of 0's
    //adn[threadIdx.x] = threadIdx.x;

}

int main()
{

    const int adnLength = NUMCROMOSOMAS * SIZECROMOSOMAS; // 256 * 128 (32.768)
    const size_t adnSize = adnLength * sizeof(int);
    int adnCPU[adnLength];
    int * adnDevice;

    cudaError_t error = cudaSetDevice(0);
    if (error != cudaSuccess) 
        exit(-EXIT_FAILURE);

    curandState * randState;
    error = cudaMalloc(&randState, adnLength * sizeof(curandState));
    if (error != cudaSuccess){
        cudaFree(randState);
        exit(-EXIT_FAILURE);
    }
    //Here is initialized cuRand
    setup_cuRand <<<1, adnLength >> > (randState, unsigned(time(NULL)));

    error = cudaMalloc((void **)&adnDevice, adnSize);

    if (error == cudaErrorMemoryAllocation){// cudaSuccess){
        cudaFree(adnDevice);
        cudaFree(randState);
        printf("\n error");
        exit(-EXIT_FAILURE);
    }


    poblar <<<1, adnLength >>> (adnDevice, randState);
    error = cudaMemcpy(adnCPU, adnDevice, adnSize, cudaMemcpyDeviceToHost);
    //After here, for any i, adnCPU[i] is 0 and i cannot figure what is wrong
    if (error == cudaSuccess){
        for (int i = 0; i < NUMCROMOSOMAS; i++){
            for (int j = 0; j < SIZECROMOSOMAS; j++){
                printf("%i,", adnCPU[(i*SIZECROMOSOMAS) + j]);
            }
            printf("\n");
        }
    }

    return 0;
}

但问题是输出是一些奇怪的符号而不是文件的文本是＆＃34;这只是一个测试＆＃34;。为什么会发生这种情况？

Answer 1

可能的原因包括：

fopen无法打开指定的文件。通过检查i。
请参阅Why is “while ( !feof (file) )” always wrong?
您始终打印100个字符，但如果文件包含少于100个字符，则会因为打印阵列的未初始化位置而导致UB出现问题。通过打印从零开始到int i = 0, j = 0; char A[1000]; FILE* fpointer; fpointer = fopen("text.txt", "r"); if(!fpointer) { fputs("fopen failed! Exiting...\n", stderr); exit(-1); /* Requires `stdlib.h` */ } while(fscanf(fpointer, "%c", &A[i]) != EOF) { i = i + 1; } fclose(fpointer); for (j = 0; j < i; j++){ printf("A[%d] = '%c'\n", j, A[j]); }的所有内容进行修复。

更正了代码段：

{{1}}

Answer 2

展开points by @Cool Guy：

如果您的文件不包含null character，则可以避免使用其他变量来存储读取的字符数。如果null终止读入的字符，则可以直接将它们打印为字符串。

您必须确保A可以容纳足够的字符。如果您预计最多1000个字符，请确保A的大小为1001字节以包含终止NUL字符。

#include <stdio.h>
#include <stdlib.h>

int main(int argc, char **argv)
{
    char A[1001] = { 0 }; /* init to NUL, expect at most 1000 chars */
    int i;    
    FILE *fpointer;

    fpointer=fopen("text.txt","r");
    if(!fpointer) {
        perror("Error opening file"); /* print error message */
        exit(-1); /* Requires `stdlib.h` */
    }
    /* read all characters from fpointer into A */
    for (i=0; fscanf(fpointer, "%c", &A[i]) != EOF; i++);
    fclose(fpointer);

    printf("%s\n",A); /* print all characters as a string */

    /* alternatively, loop until NUL found */
    for (i=0; A[i]; i++)
        printf("%c", A[i]);
    printf("\n");

    return 0;
}

使用fscanf（）从文件中读取文本

2 个答案: