Question

我正在做一个练习，其中根据其主题和人数将某些班级划分为上级或下级。我可以对上层和下层类进行正确的分类，但是我的输出似乎是列表列表。下面是预期的输出，它只是一个列表。我的代码基于我到目前为止在模块中学到的方法。

预期产量

['PSYCH 412', 'MATH 300', 'MATH 404', 'ENG 201', 'PSYCH 508', 'ENG 220']

有人可以帮助我弄清楚如何将我的输出显示为列表而不是列表吗？谢谢。

classes = ["MATH 150", "PSYCH 111", "PSYCH 313", "PSYCH 412", "MATH 300", "MATH 404", "MATH 206", "ENG 100", "ENG 103", "ENG 201", "PSYCH 508", "ENG 220", "ENG 125", "ENG 124"]
upper = [] #empty list
lower = [] #empty list

for w in classes:
    sub = w.split()
    if "MATH" in sub and int(sub[1]) >= 300:
        upper.append(sub)
    elif "ENG" in sub and int(sub[1]) >= 200:
        upper.append(sub)
    elif "PSYCH" in sub and int(sub[1]) >= 400:
        upper.append(sub)
    else:
        lower.append(sub)

print("Upper Level Courses:", upper)

我的输出

Upper Level Courses: [['PSYCH', '412'], ['MATH', '300'], ['MATH', '404'], ['ENG', '201'], ['PSYCH', '508'], ['ENG', '220']]

Answer 1

您的解决方案已接近尾声，而不是将sub附加w到upper或lower：

classes = ["MATH 150", "PSYCH 111", "PSYCH 313", "PSYCH 412", "MATH 300", "MATH 404", "MATH 206", "ENG 100", "ENG 103", "ENG 201", "PSYCH 508", "ENG 220", "ENG 125", "ENG 124"]
upper = [] #empty list
lower = [] #empty list

for w in classes:
    sub = w.split()
    if "MATH" in sub and int(sub[1]) >= 300:
        upper.append(w)
    elif "ENG" in sub and int(sub[1]) >= 200:
        upper.append(w)
    elif "PSYCH" in sub and int(sub[1]) >= 400:
        upper.append(w)
    else:
        lower.append(w)

print("Upper Level Courses:", upper)

打印：

Upper Level Courses: ['PSYCH 412', 'MATH 300', 'MATH 404', 'ENG 201', 'PSYCH 508', 'ENG 220']

Answer 2

因为sub对象是列表类型，所以在结果中它是列表。您可以将子列表集中为一个字符串，或者只使用w对象，然后将其追加到上/下列表中。

classes = ["MATH 150", "PSYCH 111", "PSYCH 313", "PSYCH 412", "MATH 300", "MATH 404", "MATH 206", "ENG 100", "ENG 103", "ENG 201", "PSYCH 508", "ENG 220", "ENG 125", "ENG 124"]
upper = [] #empty list
lower = [] #empty list

for w in classes:
    sub = w.split()
    if "MATH" in sub and int(sub[1]) >= 300:
        upper.append(" ".join(sub))
    elif "ENG" in sub and int(sub[1]) >= 200:
        upper.append(" ".join(sub))
    elif "PSYCH" in sub and int(sub[1]) >= 400:
        upper.append(" ".join(sub))
    else:
        lower.append(" ".join(sub))

print("Upper Level Courses:", upper)

您还可以使用List Comprehensions来重写代码，如下所示：

classes = ["MATH 150", "PSYCH 111", "PSYCH 313", "PSYCH 412", "MATH 300", "MATH 404", "MATH 206", "ENG 100", "ENG 103", "ENG 201", "PSYCH 508", "ENG 220", "ENG 125", "ENG 124"]

upper = [c for c in classes if ("MATH" in c and int(c.split()[1])>=300) or ("ENG" in c and int(c.split()[1])>=200) or ("PSYCH" in c and int(c.split()[1])>=400) ]
lower = [c for c in classes if c not in upper]

希望有帮助。

如何打印列表而不是列表

2 个答案: