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Captured variable in a loop in C#
...riencing is something known as Closure http://en.wikipedia.org/wiki/Closure_(computer_science). Your lamba has a reference to a variable which is scoped outside the function itself. Your lamba is not interpreted until you invoke it and once it is it will get the value the variable has at execution t...
Get color value programmatically when it's a reference (theme)
...edValue, true);
@ColorInt int color = typedValue.data;
Also make sure to apply the theme to your Activity before calling this code. Either use:
android:theme="@style/Theme.BlueTheme"
in your manifest or call (before you call setContentView(int)):
setTheme(R.style.Theme_BlueTheme)
in onCreat...
Pandas every nth row
...simpler solution to the accepted answer that involves directly invoking df.__getitem__.
df = pd.DataFrame('x', index=range(5), columns=list('abc'))
df
a b c
0 x x x
1 x x x
2 x x x
3 x x x
4 x x x
For example, to get every 2 rows, you can do
df[::2]
a b c
0 x x x
...
How can I make git ignore future revisions to a file?
...ten by checkout: , even -f does not help error: Entry 'wix-stores-merchant-app/demo/credentials.js' not uptodate. Cannot merge.
– ykravv
Nov 28 '19 at 9:02
...
What does numpy.random.seed(0) do?
...
If you set the np.random.seed(a_fixed_number) every time you call the numpy's other random function, the result will be the same:
>>> import numpy as np
>>> np.random.seed(0)
>>> perm = np.random.permutation(10)
>>> p...
How do I get around type erasure on Scala? Or, why can't I get the type parameter of my collections?
...mport scala.reflect.Manifest
private var map= Map.empty[Any,(Manifest[_], Any)]
def register[T](name: Any, item: T)(implicit m: Manifest[T]) {
map = map.updated(name, m -> item)
}
def get[T](key:Any)(implicit m : Manifest[T]): Option[T] = {
map get key flatMap {
ca...
What is mattr_accessor in a Rails module?
... couldn't really find this in Rails documentation but it seems like 'mattr_accessor' is the Module corollary for 'attr_accessor' (getter & setter) in a normal Ruby class .
...
What is the difference between 127.0.0.1 and localhost
...
some applications will treat "localhost" specially. the mysql client will treat localhost as a request to connect to the local unix domain socket instead of using tcp to connect to the server on 127.0.0.1. This may be faster, an...
Read error response body in Java
...ere is to code like this:
HttpURLConnection httpConn = (HttpURLConnection)_urlConnection;
InputStream _is;
if (httpConn.getResponseCode() < HttpURLConnection.HTTP_BAD_REQUEST) {
_is = httpConn.getInputStream();
} else {
/* error from server */
_is = httpConn.getErrorStream();
}
...
CSV new-line character seen in unquoted field error
...csv file itself, but this might work for you, give it a try, replace:
file_read = csv.reader(self.file)
with:
file_read = csv.reader(self.file, dialect=csv.excel_tab)
Or, open a file with universal newline mode and pass it to csv.reader, like:
reader = csv.reader(open(self.file, 'rU'), dialec...