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How to delete multiple values from a vector?
...ude it for the sake of readability.
This is, btw., what setdiff does internally (but without the unique to throw away duplicates in a which are not in remove).
If remove contains incomparables, you'll have to check for them individually, e.g.
if (any (is.na (remove)))
a <- a [! is.na (a)]
(...
How to get the error message from the error code returned by GetLastError()?
After a Windows API call, how can I get the last error message in a textual form?
11 Answers
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Why does the order of the loops affect performance when iterating over a 2D array?
... x[1][0] etc...
Meaning that you're hitting them all in order. Now look at the 1st version. You're doing:
x[0][0]
x[1][0]
x[2][0]
x[0][1]
...
Python - Create list with numbers between 2 values?
...
Use range. In Python 2.x it returns a list so all you need is:
>>> range(11, 17)
[11, 12, 13, 14, 15, 16]
In Python 3.x range is a iterator. So, you need to convert it to a list:
>>> list(range(11, 17))
[11, 12, 13, 14, 15, 16]
Note: The second nu...
How to determine whether code is running in DEBUG / RELEASE build?
...EBUG changed to another variable name such as DEBUG_MODE.
then conditionally code for DEBUG in your source files
#ifdef DEBUG
// Something to log your sensitive data here
#else
//
#endif
share
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Why is lazy evaluation useful?
...epending on the sequence of conditional expressions, only a subset may actually be used. In a language like C, all three values would be computed anyway; but in Haskell, only the necessary values are computed.
It also allows for cool stuff like infinite lists. I can't have an infinite list in a lan...
How dangerous is it to compare floating point values?
...
First of all, floating point values are not "random" in their behavior. Exact comparison can and does make sense in plenty of real-world usages. But if you're going to use floating point you need to be aware of how it works. Erring on...
Does this app use the Advertising Identifier (IDFA)? - AdMob 6.8.0
...it Ad Tracking.
Including Limit Ad Tracking. This is what the last box is all about. So you must check the that box if you use AdMob. If you use other SDK I strongly recommend checking if they respect the guidelines as well.
Since I run only ads (Google AdMob), I checked the first (Serve ads...) a...
Force CloudFront distribution/file update
...
Good news. Amazon finally added an Invalidation Feature. See the API Reference.
This is a sample request from the API Reference:
POST /2010-08-01/distribution/[distribution ID]/invalidation HTTP/1.0
Host: cloudfront.amazonaws.com
Authorization:...
Why does C++ require a user-provided default constructor to default-construct a const object?
...
This was considered a defect (against all versions of the standard) and it was resolved by Core Working Group (CWG) Defect 253. The new wording for the standard states in http://eel.is/c++draft/dcl.init#7
A class type T is const-default-constructible if
def...