高效 python (3)

三支股票两日收盘价格如下，求价格波动率：

	s1	s2	s3
day1	10.1	32.92	123.45
day2	10.31	33.17	119.11

C:

#include <stdio.h>

#define NROFST 3
int main()
{
        float day1[NROFST] = {10.1, 32.92, 123.45};
        float day2[NROFST] = {10.31, 33.17, 119.11};

        for (int i = 0; i < NROFST; i++){
                printf("%f\%, ", (day2[i] - day1[i]) / day1[i] * 100);
        }
        printf("\n");

        return 0;
}

result:


python:

from decimal import Decimal

day1 = map(Decimal, map(str, [10.1, 32.92, 123.45]))
day2 = map(Decimal, map(str, [10.31, 33.17, 119.11]))

x = map(lambda x, y: (y - x) / x * 100, day1, day2)

print(x)
print(map(str, x))
print(map(lambda s : s[:6], map(str, x)))
print(map(float, x))

result:

map(function, sequence) ：对sequence中的item依次执行function(item)，将执行结果组成一个List返回.