在Python中查找子字符串

Question

I have found synonyms of a word "plant"

syn = wordnet.synsets('plant')[0].lemmas()
>>>[Lemma('plant.n.01.plant'), Lemma('plant.n.01.works'), Lemma('plant.n.01.industrial_plant')]

and an input word

word = 'work'

I want to find if 'work' appears in syn. How to do it?

Answer 1

You can easily check for the presence of a substring using the keyword in in python:

>>> word = "work"
>>> word in 'plant.n.01.works'
True
>>> word in 'plant.n.01.industrial_plant'
False

If you want to test this in a list you can do a loop:

syn = ["plant.one","plant.two"]
for plant in syn:
    if word in plant:
        print("ok")

Or better a list comprehension:

result = [word in plant for plant in syn]
# To get the number of matches, you can sum the resulting list:
sum(result)

Edit : If you have a long list of words to look for, you can just nest two loops:

words_to_search = ["work","spam","foo"]
syn = ["plant.one","plant.two"]
for word in words_to_search_for:
    if sum([word in plant for plant in syn]):
        print("{} is present in syn".format(word))

---

Note that you are manipulating Lemma objects and not strings. You might need to check for word in plant.name instead of just word if the object do not implement the [__contains__](https://docs.python.org/2/library/operator.html#operator.__contains__) method. I am not familiar with this library though.

Answer 2

Lemma 's have a name() method so what you could do is

>>> 'works' in map(lambda x: x.name(), syn)
True

Edit: did not see you said "work", not works, so this would be:

>>> for i in syn:
...     if 'work' in i.name():
...             print True
... 
True

You can wrap it in a function for example.

Or a mixture of the two suggestions I made:

any(map(lambda x: 'work' in x, map(lambda x: x.name(), syn)))

Answer 3

str1 = "this is a example , xxx"
str2 = "example"
target_len = len(str2)
str_start_position = str1.index(str2)  #or  str1.find(str2)
str_end_position = str_start_position + target_len

you can use str_start_position and str_end_position to get your target substring