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super() fails with error: TypeError “argument 1 must be type, not classobj” when parent does not inh
...nk your python version is 2.X, the super would work when adding this code
__metaclass__ = type
so the code is
__metaclass__ = type
class B:
def meth(self, arg):
print arg
class C(B):
def meth(self, arg):
super(C, self).meth(arg)
print C().meth(1)
...
What is getattr() exactly and how do I use it?
...answered Apr 10 '19 at 9:42
blue_noteblue_note
21k55 gold badges3737 silver badges6262 bronze badges
...
Difference between reduce and foldLeft/fold in functional programming (particularly Scala and Scala
...ase of foldLeft
scala> val intParList: ParSeq[Int] = (1 to 100000).map(_ => scala.util.Random.nextInt()).par
scala> timeMany(1000, intParList.reduce(_ + _))
Took 462.395867 milli seconds
scala> timeMany(1000, intParList.foldLeft(0)(_ + _))
Took 2589.363031 milli seconds
reduce vs fo...
Will the base class constructor be automatically called?
...ered Oct 31 '12 at 19:21
Science_FictionScience_Fiction
3,2131414 silver badges2424 bronze badges
...
What's the dSYM and how to use it? (iOS SDK)
... 0x000000018f3c9380 closure #1 in closure #1 in closure #1 in _assertionFailure+ 217984 (_:_:file:line:flags:) + 452
1 libswiftCore.dylib 0x000000018f3c9380 closure #1 in closure #1 in closure #1 in _assertionFailure+ 217984 (_:_:file:line:flags:) + 452
2 libswiftCore.d...
How to add an extra column to a NumPy array
...
np.r_[ ... ] and np.c_[ ... ]
are useful alternatives to vstack and hstack,
with square brackets [] instead of round ().
A couple of examples:
: import numpy as np
: N = 3
: A = np.eye(N)
: np.c_[ A, np.ones(N) ] #...
background function in Python
...
Do something like this:
def function_that_downloads(my_args):
# do some long download here
then inline, do something like this:
import threading
def my_inline_function(some_args):
# do some stuff
download_thread = threading.Thread(target=function_t...
Does use of final keyword in Java improve the performance?
...(at compile time).
public class FinalTest {
public static final int N_ITERATIONS = 1000000;
public static String testFinal() {
final String a = "a";
final String b = "b";
return a + b;
}
public static String testNonFinal() {
String a = "a";
...
Real world example about how to use property feature in python?
...changing terms.
Complex calculation hidden behind an attribute:
class PDB_Calculator(object):
...
@property
def protein_folding_angle(self):
# number crunching, remote server calls, etc
# all results in an angle set in 'some_angle'
# It could also reference a ca...
How do I print to the debug output window in a Win32 app?
... either maps to OutputDebugStringA(char const*) or OutputDebugStringW(wchar_t const*). In the later case you will have to supply a wide character string to the function. To create a wide character literal you can use the L prefix:
OutputDebugStringW(L"My output string.");
Normally you will use th...