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Scala equivalent of Java java.lang.Class Object
...: java.lang.Class[C] = class C
scala> c.getClass
res1: java.lang.Class[_] = class C
That is why the following will not work:
val xClass: Class[X] = new X().getClass //it returns Class[_], nor Class[X]
val integerClass: Class[Integer] = new Integer(5).getClass //similar error
There is a ticket...
Apply multiple functions to multiple groupby columns
...ame, you can use a normal function and supply a custom name to the special __name__ attribute like this:
def max_min(x):
return x.max() - x.min()
max_min.__name__ = 'Max minus Min'
df.groupby('group').agg({'a':['sum', 'max'],
'b':'mean',
'c'...
How to access session variables from any class in ASP.NET?
I have created a class file in the App_Code folder in my application. I have a session variable
7 Answers
...
Locking a file in Python
...file locking (Linux, Ubuntu, MacOS, etc.)
import fcntl, os
def lock_file(f):
fcntl.lockf(f, fcntl.LOCK_EX)
def unlock_file(f):
fcntl.lockf(f, fcntl.LOCK_UN)
except ModuleNotFoundError:
# Windows file locking
import msvcrt, os
def file_size(f):
return o...
Link to all Visual Studio $ variables
... on my machine. Probably not all macros are defined for others (e.g. OCTAVE_EXECUTABLE), but I wanted to err on the side of inclusiveness here.
For example, this is the first time that I see $(Language) (expanding to C++ for this project) being mentioned outside of the IDE.
$(AllowLocalNetworkLoop...
Converting a view to Bitmap without displaying it in Android?
...( v.getLayoutParams().width, v.getLayoutParams().height, Bitmap.Config.ARGB_8888);
Canvas c = new Canvas(b);
v.layout(v.getLeft(), v.getTop(), v.getRight(), v.getBottom());
v.draw(c);
return b;
}
if the view wasn't displayed before the size of it will be zero. Its p...
How to log source file name and line number in Python
...='%Y-%m-%d:%H:%M:%S',
level=logging.DEBUG)
logger = logging.getLogger(__name__)
logger.debug("This is a debug log")
logger.info("This is an info log")
logger.critical("This is critical")
logger.error("An error occurred")
Generates this output:
2017-06-06:17:07:02,158 DEBUG [log.py:11] Thi...
Unsupported major.minor version 52.0 [duplicate]
...l Java 1.5 and is nowadays called "Java SE", see en.wikipedia.org/wiki/Java_Platform,_Standard_Edition
– Tim Büthe
Sep 6 '16 at 14:38
1
...
“is” operator behaves unexpectedly with integers
...tively rare. Here's an example (will work in Python 2 and 3) e.g.
SENTINEL_SINGLETON = object() # this will only be created one time.
def foo(keyword_argument=None):
if keyword_argument is None:
print('no argument given to foo')
bar()
bar(keyword_argument)
bar('baz')
def b...
Best practices for in-app database migration for Sqlite
...t/set this variable with the following sqlite statements:
> PRAGMA user_version;
> PRAGMA user_version = 1;
When the app starts, I check the current user-version, apply any changes that are needed to bring the schema up to date, and then update the user-version. I wrap the updates in a t...