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How do I replace NA values with zeros in an R dataframe?
...then assign it to the location/name on the left. In this case, we aren't really "doing" anything - just making zeroes. The left side is saying: look at the d object, inside the d object (the square brackets), find all the elements that return TRUE (is.na(d) returns a logical for each element). Once...
When should use Readonly and Get only properties
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edited Nov 16 '16 at 18:37
bwegs
3,69122 gold badges2626 silver badges3131 bronze badges
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How to set default value for form field in Symfony2?
..., it will also always force the value under any context. Not what I would call a "default value"...
– Hubert Perron
Apr 3 '13 at 18:25
4
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Post JSON using Python Requests
...late',
'Connection': 'close',
'Content-Length': '16',
'Content-Type': 'application/json',
'Host': 'httpbin.org',
'User-Agent': 'python-requests/2.4.3 CPython/3.4.0',
'X-Request-Id': 'xx-xx-xx'},
'json': {'key': 'value'},
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How can I reliably get an object's address when operator& is overloaded?
...argument and returning no result. This reference to a function can be trivially converted into a pointer to function -- from @Konstantin: According to 13.3.3.2 both T & and T * are indistinguishable for functions. The 1st one is an Identity conversion and the 2nd one is Function-to-Pointer conve...
What is the difference between JavaConverters and JavaConversions in Scala?
...eating wrappers that implement either the Scala interface and forward the calls to the underlying Java collection, or the Java interface, forwarding the calls to the underlying Scala collection.
JavaConverters uses the pimp-my-library pattern to “add” the asScala method to the Java collections ...
How to dismiss keyboard for UITextView with return key?
...urn key is pressed, the keyboard for UITextView will disappear. But actually the return key can only act as '\n'.
34 ...
How should one use std::optional?
...std::string s, int& i);
Another way that this could be done is especially bad:
int* try_parse_int(std::string s); //return nullptr if fail
This requires dynamic memory allocation, worrying about ownership, etc. - always prefer one of the other two signatures above.
Another example:
clas...
How to install the Raspberry Pi cross compiler on my Linux host machine?
...ge up and copy it via rsync:
rsync -rl --delete-after --safe-links pi@192.168.1.PI:/{lib,usr} $HOME/raspberrypi/rootfs
where 192.168.1.PI is replaced by the IP of your Raspberry Pi.
Now, we need to write a cmake config file. Open ~/home/raspberrypi/pi.cmake in your favorite editor and insert the...
In PowerShell, how do I define a function in a file and call it from the PowerShell commandline?
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What you are talking about is called dot sourcing. And it's evil. But no worries, there is a better and easier way to do what you are wanting with modules (it sounds way scarier than it is). The major benefit of using modules is that you can unload them fr...