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Difference between as.POSIXct/as.POSIXlt and strptime for converting character vectors to POSIXct/PO
... great answer. is there a consensus on which is best practice for compiling data for modeling or data visualization purposes?
– dre
Dec 26 '18 at 15:54
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When should null values of Boolean be used?
...ooleans in a collection (List, Map, etc.)
to represent a nullable boolean (coming from a nullable boolean column in a database, for example). The null value might mean "we don't know if it's true or false" in this context.
each time a method needs an Object as argument, and you need to pass a boolea...
What is the difference between NTFS Junction Points and Symbolic Links?
...c link for its added abilities.
**The statement of difference in speed/complexity comes from an unverified statement in the Wikipedia entry on NTFS reparse points (a good read).*
Other NTFS Link Comparisons
Here are some other comparisons on the topic, but these can be misleading when consid...
How to post data in PHP using file_get_contents?
...stream_context_create($opts);
$result = file_get_contents('http://example.com/submit.php', false, $context);
Basically, you have to create a stream, with the right options (there is a full list on that page), and use it as the third parameter to file_get_contents -- nothing more ;-)
As a sideno...
Right to Left support for Twitter Bootstrap 3
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I highly recommend bootstrap-rtl. It is built over Bootstrap core, and rtl support is added as it is a bootstrap theme. This would make your code more maintainable as you can always update your core bootstrap files. CDN
Another option t...
How do I write a correct micro-benchmark in Java?
...test kernel all the way through, enough to trigger all initializations and compilations before timing phase(s). (Fewer iterations is OK on the warmup phase. The rule of thumb is several tens of thousands of inner loop iterations.)
Rule 2: Always run with -XX:+PrintCompilation, -verbose:gc, etc., so...
What is Erlang written in?
What is Ericsson's implementation of Erlang and Erlang/OTP written and compiled in? Is is assembly, C or Erlang itself?
4 A...
Scripting TFS Command Line for Get Latest Version, Check Out and Check in, programmatically
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Use tf.exe in the command line.
In the following examples, the %PathToIde% is usually on a path like this: %ProgramFiles%\Microsoft Visual Studio 9.0\Common7\IDE, or on Windows x64: %ProgramFiles(x86)%\Microsoft Visual Studio 10.0\Common7\IDE...
How do I get into a non-password protected Java keystore or change the password?
..."changeme" up to a certain point. Apparently as of Mountain Lion (based on comments and another answer here), the password for Mac is now also "changeit", probably because Oracle is now handling distribution for the Mac JVM as well.
...
django admin - add custom form fields that are not part of the model
...forms.ModelForm):
extra_field = forms.CharField()
def save(self, commit=True):
extra_field = self.cleaned_data.get('extra_field', None)
# ...do something with extra_field here...
return super(YourModelForm, self).save(commit=commit)
class Meta:
model = ...