短路和浮动

Question

我试图在 Python 中使用短路来打印一些数据，但尽管我写了 .2f

，但我的浮点数并没有在点后出现 2 个数字

((DidHourPlus == 1) and (StartWeek == 1) and (post == "r") and print("The daily salary is %2.f" %  ((hours - 8) * 35 + 8 * 30)))
((DidHourPlus == 1) and (StartWeek == 1) and (post == "s") and print("The daily salary is %2.f" % (1.20*((hours - 8) * 35 + 8 * 30))))
((DidHourPlus == 1) and (StartWeek == 1) and (post == "m") and print("The daily salary is %2.f" % (1.50*((hours - 8) * 35 + 8 * 30))))

Answer 1

这是误用短路。不要这样使用 and。使用 if 语句。

对于两位小数，将 2 放在小数点后：%.2f 而不是 %2.f。

if DidHourPlus == 1 and StartWeek == 1 and post == "r": print("The daily salary is %.2f" %  ((hours - 8) * 35 + 8 * 30)))
if DidHourPlus == 1 and StartWeek == 1 and post == "s": print("The daily salary is %.2f" % (1.20*((hours - 8) * 35 + 8 * 30)))
if DidHourPlus == 1 and StartWeek == 1 and post == "m": print("The daily salary is %.2f" % (1.50*((hours - 8) * 35 + 8 * 30)))

您可以将重复的测试提取到单个 if:

if DidHourPlus == 1 and StartWeek == 1:
    if post == "r": print("The daily salary is %.2f" %  ((hours - 8) * 35 + 8 * 30)))
    if post == "s": print("The daily salary is %.2f" % (1.20*((hours - 8) * 35 + 8 * 30)))
    if post == "m": print("The daily salary is %.2f" % (1.50*((hours - 8) * 35 + 8 * 30)))

然后提取打印输出：

if DidHourPlus == 1 and StartWeek == 1:
    salary = None

    if post == "r": salary = (hours - 8) * 35 + 8 * 30
    if post == "s": salary = 1.20*((hours - 8) * 35 + 8 * 30)
    if post == "m": salary = 1.50*((hours - 8) * 35 + 8 * 30)

    if salary:
        print("The daily salary is %.2f" % salary)

然后提取工资计算：

if DidHourPlus == 1 and StartWeek == 1:
    rate = None

    if post == "r": rate = 1.00
    if post == "s": rate = 1.20
    if post == "m": rate = 1.50

    if rate:
        salary = rate * ((hours - 8) * 35 + 8 * 30)
        print("The daily salary is %.2f" % salary)

你可以到此为止，但如果你想变得更高级，你可以在字典中查找费率。

if DidHourPlus == 1 and StartWeek == 1:
    rates = {"r": 1.00, "s": 1.20, "m": 1.50}
    rate  = rates.get(post)

    if rate:
        salary = rate * ((hours - 8) * 35 + 8 * 30)
        print("The daily salary is %.2f" % salary)

在 Python 3.8 中，您可以使用 assignment expression.

进一步收紧它

if DidHourPlus == 1 and StartWeek == 1:
    rates = {"r": 1.00, "s": 1.20, "m": 1.50}

    if rate := rates.get(post):
        salary = rate * ((hours - 8) * 35 + 8 * 30)
        print("The daily salary is %.2f" % salary)

短路和浮动

Short-Circuit And Float

python

short

short-circuiting