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What does axis in pandas mean?
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I think the confusion comes from the complexity of each so-called "act". df.dropna(axis=0) will first check all the COLUMNS in each ROW and then drop those ROWS with a null. The axis talks about the last step but our brain will focus on the first part....
How to create a new branch from a tag?
I'd like to create a new master branch from an existing tag. Say I have a tag v1.0 . How to create a new branch from this tag?
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static function in C
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Making a function static hides it from other translation units, which helps provide encapsulation.
helper_file.c
int f1(int); /* prototype */
static int f2(int); /* prototype */
int f1(int foo) {
return f2(foo); /* ok, f2 is in the same translat...
Remove excess whitespace from within a string
I receive a string from a database query, then I remove all HTML tags, carriage returns and newlines before I put it in a CSV file. Only thing is, I can't find a way to remove the excess white space from between the strings.
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extract part of a string using bash/cut/split
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To extract joebloggs from this string in bash using parameter expansion without any extra processes...
MYVAR="/var/cpanel/users/joebloggs:DNS9=domain.com"
NAME=${MYVAR%:*} # retain the part before the colon
NAME=${NAME##*/} # retain the part...
When should we use intern method of String on String literals
...ing to String#intern() , intern method is supposed to return the String from the String pool if the String is found in String pool, otherwise a new string object will be added in String pool and the reference of this String is returned.
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PHP: Convert any string to UTF-8 without knowing the original character set, or at least try
I have an application that deals with clients from all over the world, and, naturally, I want everything going into my databases to be UTF-8 encoded.
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The static keyword and its various uses in C++
...e scope (i.e. outside of functions and classes), then it can't be accessed from any other translation unit. This is known as "internal linkage" or "static storage duration". (Don't do this in headers except for constexpr. Anything else, and you end up with a separate variable in each translation un...
How to count TRUE values in a logical vector
... My reply is just too long, so I posted a new answer, since it differs from previous one.
– aL3xa
Feb 5 '10 at 18:25
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Fundamental difference between Hashing and Encryption algorithms
...d a (usually) fixed length (or smaller length) output. It can be anything from a simple crc32, to a full blown cryptographic hash function such as MD5 or SHA1/2/256/512. The point is that there's a one-way mapping going on. It's always a many:1 mapping (meaning there will always be collisions) si...