Python:字符串比较

Question

这里我有一个和弦列表:

chordList = ["N","C:maj","C:min","C#:maj","C#:min","D:maj","D:min","D#:maj","D#:min","E:maj","E:min","F:maj","F:min","F#:maj","F#:min","G:maj","G:min","G#:maj","G#min","A:maj","A:min","A#:maj", "A#:min", "B:maj","B:min"]

例如，有一些字符串，例如“F:maj”，“F:maj/3”，“C:maj/4”，“D:min7”等。我知道我可以在chordList中使用if字符串检查列表中是否有正常的和弦。但是，我想将“F:maj/3”、“C:maj/4”等字符串与列表中的字符串进行比较，无论它们是否具有共同的“x:maj”或“x:min”部分，然后返回 TRUE 或 FALSE 值

Answer 1

我建议将您的 chordList 转换为 set，以获得平均 O(1) 查找时间。

选项 1
在 / 上分割:

sample = 'C:maj/7'
sample.split('/')[0] in chordList
# True

选项 2(如果我弹钢琴的日子没记错的话，这将始终有效，尽管如果和弦存在于九度以上，这将失败)
切片

sample = 'C:maj/7'
sample[:-2] in chordList
# True