我有一个变量，里面有各种句子：
Cats are good pets, for they are clean and are not noisy.
Abstraction is often one floor above you.
She wrote a long letter to Charlie, but he didn't read it.
Where do random thoughts come from?
Mary plays the piano.
I want more detailed information.
I'd rather be a bird than a fish.
When I was little I had a car door slammed shut on my hand. I still remember it quite vividly.
Malls are great places to shop; John can find everything he needs under one roof.
My Mum tries to be cool by saying that she likes all the same things that I do.
如果找到名称，如何创建变量name == 1？
如果句子中的任何单词与我选择的单词匹配(例如letter(，我也希望有变量name == 2。
我尝试了以下方法：
gen name = regexm(sentence, "letter* & (Charlie | Mary | John)*")`
然而，这是行不通的。我在所有的观测中只得到name == 0。
正则表达式很棒，但第二十二条军规是你必须非常努力地学习语言；如果你精通了，你就会看到好处。
我将把它留给其他答案来给出智能regex解决方案。这里的目的是强调其他字符串函数也是可用的。在这里，我利用了这样一个事实：如果strpos()在另一个字符串中找到一个字符串，它将返回一个正结果，相当于true。此外，Stata将解析为单词，因此从第一原理来看，即使(例如(找到字符串当且仅当它是单词也不太困难。
clear
input strL whatever
"Cats are good pets, for they are clean and are not noisy."
"Abstraction is often one floor above you."
"She wrote a long letter to Charlie, but he didn't read it."
"Where do random thoughts come from?"
"Mary plays the piano."
"I want more detailed information."
"I'd rather be a bird than a fish."
"When I was little I had a car door slammed shut on my hand. I still remember it quite vividly."
"Malls are great places to shop; John can find everything he needs under one roof."
"My Mum tries to be cool by saying that she likes all the same things that I do."
end
gen wanted1 = strpos(whatever, "Charlie") | strpos(whatever, "Mary") | strpos(whatever, "John")
* cat or cats as a word
gen wanted2 = 0
gen wordcount = wordcount(whatever)
su wordcount, meanonly
local J = r(max)
quietly foreach w in cat cats {
forval j = 1/`J' {
replace wanted2 = 1 if word(lower(whatever), `j') == "`w'"
}
}
gen what = substr(whatever, 1, 40)
list wanted? what, sep(0)
+--------------------------------------------------------------+
| wanted1 wanted2 what |
|--------------------------------------------------------------|
1. | 0 1 Cats are good pets, for they are clean a |
2. | 0 0 Abstraction is often one floor above you |
3. | 1 0 She wrote a long letter to Charlie, but |
4. | 0 0 Where do random thoughts come from? |
5. | 1 0 Mary plays the piano. |
6. | 0 0 I want more detailed information. |
7. | 0 0 I'd rather be a bird than a fish. |
8. | 0 0 When I was little I had a car door slamm |
9. | 1 0 Malls are great places to shop; John can |
10. | 0 0 My Mum tries to be cool by saying that s |
+--------------------------------------------------------------+