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Right way to reverse pandas.DataFrame?
...ata.Odd[idx])
You are getting an error because reversed first calls data.__len__() which returns 6. Then it tries to call data[j - 1] for j in range(6, 0, -1), and the first call would be data[5]; but in pandas dataframe data[5] means column 5, and there is no column 5 so it will throw an exceptio...
dplyr: “Error in n(): function should not be called directly”
...ction" specification, like example below:
delay <- dplyr::summarise(by_tailnum,
count = n(),
dist = mean(distance, na.rm = TRUE),
delay = mean(arr_delay, na.rm = TRUE))
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improv...
A fast method to round a double to a 32-bit int explained
... this:
and it can be seen as two 32-bit integers; now, the int taken in all the versions of your code (supposing it's a 32-bit int) is the one on the right in the figure, so what you are doing in the end is just taking the lowest 32 bits of mantissa.
Now, to the magic number; as you correctly ...
What is the difference between C++ and Visual C++? [duplicate]
...979 at Bell Labs as an enhancement to the C programming language and originally named "C with Classes". It was renamed to C++ in 1983.
C++ is widely used in the software industry. Some of its application domains include systems software, application software, device drivers, embedded software, high...
How to get String Array from arrays.xml file
...c class Episode7 extends ListActivity {
String[] mTestArray;
/** Called when the activity is first created. */
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Create an ArrayAdapter that will contain all list ite...
How to set top-left alignment for UILabel for iOS application?
...turn nil;
// set inital value via IVAR so the setter isn't called
_verticalAlignment = VerticalAlignmentTop;
return self;
}
-(VerticalAlignment) verticalAlignment
{
return _verticalAlignment;
}
-(void) setVerticalAlignment:(VerticalAlignment)value
{
_verticalAlignment = value...
What exactly is a reentrant function?
...
1. How is safely defined?
Semantically. In this case, this is not a hard-defined term. It just mean "You can do that, without risk".
2. If a program can be safely executed concurrently, does it always mean that it is reentrant?
No.
For example, let's have ...
Can't open config file: /usr/local/ssl/openssl.cnf on Windows [duplicate]
...
The solution is running this command:
set OPENSSL_CONF=C:\OpenSSL-Win32\bin\openssl.cfg
or
set OPENSSL_CONF=[path-to-OpenSSL-install-dir]\bin\openssl.cfg
in the command prompt before using openssl command.
Let openssl know for sure where to find its .cfg file.
Al...
How to write a UTF-8 file with Java?
...a FileOutputStream. You can then wrap this in an OutputStreamWriter, which allows you to pass an encoding in the constructor. Then you can write your data to that inside a try-with-resources Statement:
try (OutputStreamWriter writer =
new OutputStreamWriter(new FileOutputStream(PROPERT...
How do you kill a Thread in Java?
...ee this using Thread.currentThread.getThreadGroup().list(); it will prints all the threads its has and you will see multiple instances of your thread if you repeat your flow.
– AZ_
Jun 10 '11 at 14:08
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