Question

我有两个较大的循环要处理，而我宁愿用Python理解列表。那可能吗？

参加：

void gl_mean (double x,double *count, double *mean) {


    static double p;
    static int timesIn = 0; //increment times in to update *count

    timesIn++;

    //p =  x+(*mean * *count)/(*count+1);

    p += x;
    *count = (double)timesIn;
    *mean = p/(*count);//*count must be greater than 0

    //printf("%f\n",*mean);

}

int main (void) {


    double num=0.0;             //random number
    double dI=1.0;              //Counter - avoid div-by-zero, 
    double sum=0.0;             //Sum
    int i=0;

    srand(time(0));

        //for (gl_mean (num,i,sum);i<10;i++) {, this will not progress through the loops)
        //                                      because the initializer part of the for loop
        //                                      only gets called once
        for (i=0;i<10;i++)//gl_mean (num,i,sum);i<10;i++) {
        {

            num=rand() %10 + 1;    // "%10 + 1" optional to limit range from 1 to 10
            gl_mean (num,&dI,&sum);//note the use of address operator to emulate
                                   //passing a value by reference.
                                   //values for dI and sum are updated in function

            printf("%d) %f: %f\n",(int)dI, num, sum); 
            sum += num;
        //  i = (int)dI;           //update loop index with updated value
    }
}

我想要的是这样的

males = ['a', 'b']
females = ['c', 'd']

for i in males:
    print(i)
for j in females:
    print(j)

结果：

[print(i), print(j) for i, j in males, females]

Answer 1

通常，将列表理解仅用于副作用不是一个好主意。参见this question。

我想说您的当前版本是最好的方法。但是，只要有可能...

for _ in map(print, males + females):
    pass

或

[print(x) for x in males + females]

或者只是一个for循环

for x in males + females:
    print(x)

用Pythonic方式做两个未嵌套的for循环作为列表理解

1 个答案: