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pandas: multiple conditions while indexing data frame - unexpected behavior
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As you can see, the AND operator drops every row in which at least one
value equals -1. On the other hand, the OR operator requires both
values to be equal to -1 to drop them.
That's right. Remember that you're writing the condition in te...
Installing PDO driver on MySQL Linux server
...long ago, to change my code to use PDO in order to parameterize my queries and safely save HTML in the database.
6 Answers
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Using TortoiseSVN via the command line
I want to use commandline SVN options. I use TortoiseSVN, and I run several commands and I get the following error.
12 Answ...
What does the “map” method do in Ruby?
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The map method takes an enumerable object and a block, and runs the block for each element, outputting each returned value from the block (the original object is unchanged unless you use map!):
[1, 2, 3].map { |n| n * n } #=> [1, 4, 9]
Array and Range are enume...
What is the difference between inversedBy and mappedBy?
I am developing my application using Zend Framework 2 and Doctrine 2.
4 Answers
4
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Apply a function to every row of a matrix or a data frame
Suppose I have a n by 2 matrix and a function that takes a 2-vector as one of its arguments. I would like to apply the function to each row of the matrix and get a n-vector. How to do this in R?
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How to make an OpenGL rendering context with transparent background?
...chieve what I was looking for. One of the most interesting ones is AeroGL, and it shows snippets of code using a technique that was not mentioned so far, which is rendering the graphics to a device-independent bitmap (DIB).
To close this thread permanently, the source code below implements that tec...
Get first and last day of month using threeten, LocalDate
I have a LocalDate which needs to get the first and last day of the month.
How do I do that?
10 Answers
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What is the correct answer for cout
...en updated. In particular:
In a shift operator expression E1<<E2 and E1>>E2, every value computation and side-effect of E1 is sequenced before every value computation and side effect of E2.
Which means that it requires the code to produce result b, which outputs 01.
See P0145R3 Re...
Add spaces before Capital Letters
... work fine (I even voted up Martin Browns answer), but they are expensive (and personally I find any pattern longer than a couple of characters prohibitively obtuse)
This function
string AddSpacesToSentence(string text, bool preserveAcronyms)
{
if (string.IsNullOrWhiteSpace(text))
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