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What does axis in pandas mean?
...=0 along the rows (namely, index in pandas), and axis=1 along the columns. For added clarity, one may choose to specify axis='index' (instead of axis=0) or axis='columns' (instead of axis=1).
+------------+---------+--------+
| | A | B |
+------------+---------+---------
| ...
What's the fastest way to merge/join data.frames in R?
For example (not sure if most representative example though):
5 Answers
5
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How to validate date with format “mm/dd/yyyy” in JavaScript?
I want to validate the date format on an input using the format mm/dd/yyyy .
19 Answers
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Differences between Oracle JDK and OpenJDK
... [mostly to replace licensed proprietary parts / replace with more high-performance items that only work on specific OS] components without breaking the TCK compatibility.
Many vendors implemented the Java specification and got TCK passed. For example, IBM J9, Azul Zulu, Azul Zing, and Oracle JDK.
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Convert an image to grayscale in HTML/CSS
...
Support for CSS filters has landed in Webkit. So we now have a cross-browser solution.
img {
filter: gray; /* IE6-9 */
-webkit-filter: grayscale(1); /* Google Chrome, Safari 6+ & Opera 15+ */
filter: grayscale(1); ...
How do you match only valid roman numerals with a regular expression?
...
You can use the following regex for this:
^M{0,4}(CM|CD|D?C{0,3})(XC|XL|L?X{0,3})(IX|IV|V?I{0,3})$
Breaking it down, M{0,4} specifies the thousands section and basically restrains it to between 0 and 4000. It's a relatively simple:
0: <empty> ...
Javascript calculate the day of the year (1 - 366)
How do I use javascript to calculate the day of the year, from 1 - 366? For example:
22 Answers
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How can I sort arrays and data in PHP?
... values ("nat" vs. normal). See http://php.net/manual/en/array.sorting.php for an overview and links to further details.
Multi dimensional arrays, including arrays of objects
$array = array(
array('foo' => 'bar', 'baz' => 42),
array('foo' => ..., 'baz' => ...),
...
);
If y...
range() for floats
Is there a range() equivalent for floats in Python?
21 Answers
21
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Algorithm for Determining Tic Tac Toe Game Over
...in Java, and my current method of determining the end of the game accounts for the following possible scenarios for the game being over:
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