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Find the day of a week
...
To get the weekday number (0-6,Sun-Sat) from the date you can do: format(as.Date(df$date),"%w") . For the format code details see stat.berkeley.edu/~s133/dates.html
– JStrahl
Apr 24 '15 at 22:44
...
Class type check in TypeScript
...ode inside that block is safe to use as the type you think it is.
Example from the TypeScript docs:
function isFish(pet: Fish | Bird): pet is Fish {
return (<Fish>pet).swim !== undefined;
}
// Both calls to 'swim' and 'fly' are now okay.
if (isFish(pet)) {
pet.swim();
}
else {
pet.fl...
Why doesn't java.util.Set have get(int index)?
...ions which use Object-Relational Mapping (for example with Hibernate); and from all the people who replied here, Andreas Petersson is the only one who understood the real issue and offered the correct answer to it: Java is missing a UniqueList! (or you can also call it OrderedSet, or IndexedSet).
M...
how to remove css property using javascript?
...ons:
OPTION 1:
You can use removeProperty method. It will remove a style from an element.
el.style.removeProperty('zoom');
OPTION 2:
You can set it to the default value:
el.style.zoom = "";
The effective zoom will now be whatever follows from the definitions set in the stylesheets (through ...
How do I override __getattr__ in Python without breaking the default behavior?
... be called first (only works for new style classes i.e. those that inherit from object). In this case, you can preserve default behaviour like so:
class Foo(object):
def __getattribute__(self, name):
if some_predicate(name):
# ...
else:
# Default behaviou...
How to open a second activity on click of button in android app
...thod:
public void sendMessage(View view) {
Intent intent = new Intent(FromActivity.this, ToActivity.class);
startActivity(intent);
}
And the most important thing: don't forget to define your activity in manifest.xml
<activity>
android:name=".ToActivity"
android:label="...
'await' works, but calling task.Result hangs/deadlocks
...and removing same-thread guarantees provided by the SynchronizationContext from the system under test.
– Stephen Cleary
Oct 8 '15 at 10:21
69
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What are the rules for JavaScript's automatic semicolon insertion (ASI)?
...he grammar, a semicolon is inserted before it if:
The token is separated from the previous token by at least one LineTerminator.
The token is }
e.g.:
{ 1
2 } 3
is transformed to
{ 1
;2 ;} 3;
The NumericLiteral 1 meets the first condition, the following token is a line terminator...
Is it possible to have a Subversion repository as a Git submodule?
... svn:externals and git submodule that may trip you up if you approach this from a subversion point of view. The git submodule is pegged to the revision that you give it. If "upstream" changes, then you have to update your submodule's reference.
So when we resync with the upstream subversion:
cd /...
How to send POST request in JSON using HTTPClient in Android?
I'm trying to figure out how to POST JSON from Android by using HTTPClient. I've been trying to figure this out for a while, I have found plenty of examples online, but I cannot get any of them to work. I believe this is because of my lack of JSON/networking knowledge in general. I know there are ...