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Get the first element of each tuple in a list in Python [duplicate]
An SQL query gives me a list of tuples, like this:
5 Answers
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What is the difference between active and passive FTP?
...passive are the two modes that FTP can run in.
For background, FTP actually uses two channels between client and server, the command and data channels, which are actually separate TCP connections.
The command channel is for commands and responses while the data channel is for actually transferring...
How to convert an array of strings to an array of floats in numpy?
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Well, if you're reading the data in as a list, just do np.array(map(float, list_of_strings)) (or equivalently, use a list comprehension). (In Python 3, you'll need to call list on the map return value if you use map, since map returns...
What is the 'dynamic' type in C# 4.0 used for?
C# 4.0 introduced a new type called 'dynamic'. It all sounds good, but what would a programmer use it for?
10 Answers
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How do I make a list of data frames?
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This isn't related to your question, but you want to use = and not <- within the function call. If you use <-, you'll end up creating variables y1 and y2 in whatever environment you're working in:
d1 <- data.frame(y1 <- c(1, 2, 3), y2...
How do I disable form resizing for users? [duplicate]
How do I disable form resizing for users? Which property is used?
7 Answers
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Why is it bad practice to call System.gc()?
...er answering a question about how to force-free objects in Java (the guy was clearing a 1.5GB HashMap) with System.gc() , I was told it's bad practice to call System.gc() manually, but the comments were not entirely convincing. In addition, no one seemed to dare to upvote, nor downvote my ans...
How to parse/format dates with LocalDateTime? (Java 8)
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Parsing date and time
To create a LocalDateTime object from a string you can use the static LocalDateTime.parse() method. It takes a string and a DateTimeFormatter as parameter. The DateTimeFormatter is used to specify the date/time pattern.
String str = "1986-04-08 12:30";
DateTimeFormatter ...
Update multiple columns in SQL
Is there a way to update multiple columns in SQL server the same way an insert statement is used?
13 Answers
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iphone - how can i get the height and width of uiimage
... edited Jul 18 '16 at 14:33
Ryan Brodie
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answered Mar 9 '11 at 17:28
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