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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...
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...
Why should I use version control? [closed]
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Have you ever:
Made a change to code, realised it was a mistake and wanted to revert back?
Lost code or had a backup that was too old?
Had to maintain multiple versions of a product?
Wanted to see the difference between two (or more) versions of your code?
Wanted to prove that a particula...
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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Seeding the random number generator in Javascript
Is it possible to seed the random number generator (Math.random) in Javascript?
13 Answers
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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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How does the HyperLogLog algorithm work?
I've been learning about different algorithms in my spare time recently, and one that I came across which appears to be very interesting is called the HyperLogLog algorithm - which estimates how many unique items are in a list.
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How do I format a Microsoft JSON date?
...t(jsonDate.substr(6)));
The substr() function takes out the /Date( part, and the parseInt() function gets the integer and ignores the )/ at the end. The resulting number is passed into the Date constructor.
I have intentionally left out the radix (the 2nd argument to parseInt); see my comment b...
iPhone Safari Web App opens links in new window
...is launched from Home Screen, all links will open in new window in Safari (and lose full screen functionality). How can I prevent it? I couldn't find any help, only the same unanswered question.
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Benefits of using the conditional ?: (ternary) operator
What are the benefits and drawbacks of the ?: operator as opposed to the standard if-else statement. The obvious ones being:
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