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Remove duplicated rows
I have read a CSV file into an R data.frame. Some of the rows have the same element in one of the columns. I would like to remove rows that are duplicates in that column. For example:
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Convert JSON to Map
...r), you'd do:
Map<String,Object> result =
new ObjectMapper().readValue(JSON_SOURCE, HashMap.class);
(where JSON_SOURCE is a File, input stream, reader, or json content String)
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Echo newline in Bash prints literal \n
... @Okneloper Works just fine for me.
– Matthew Read
Sep 13 '17 at 20:06
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Should I use string.isEmpty() or “”.equals(string)?
... I'd say str.isEmpty() is much more clear than "".equals(str). It reads as what you're checking. Matter of opinion though, I guess.
– ColinD
Jul 23 '10 at 19:14
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UITextField border color
...nse to you, I suggest you go to a website, for example Ray Wenderlich, and read some beginner tuts.
– Aleksander
Jan 2 '15 at 14:25
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Disable LESS-CSS Overwriting calc() [duplicate]
... into the calc was super helpful. The exact follow-on question I had after reading the above accepted answer. ????
– Hynes
Jul 8 '15 at 13:22
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WebClient vs. HttpWebRequest/HttpWebResponse
...ebRequest/Response can also be accomplished with the WebClient class. I read somewhere that WebClient is a high-level wrapper for WebRequest/Response .
So far, I can't see anything that can be accomplished with HttpWebRequest/Response that can not be accomplished with WebClient , nor whe...
What is the difference between '/' and '//' when used for division?
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edited: You can "fix" division since Python 2.2! (Just read the linked PEP)
– u0b34a0f6ae
Nov 9 '09 at 23:51
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How do I determine the current operating system with Node.js
...lease()); // "10.0.14393"
console.log(os.platform()); // "win32"
You can read it's full documentation here: https://nodejs.org/api/os.html#os_os_type
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How do you debug a regex? [closed]
...can become quite complex. The lack of white space makes them difficult to read. I can't step though a regular expression with a debugger. So how do experts debug complex regular expressions?
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