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Optional Parameters with C++ Macros
...id PrintString(const char* message, int size, int style)
{
}
#define PRINT_STRING_1_ARGS(message) PrintString(message, 0, 0)
#define PRINT_STRING_2_ARGS(message, size) PrintString(message, size, 0)
#define PRINT_STRING_3_ARGS(message, size, style) PrintString(message, size, styl...
Python __str__ versus __unicode__
Is there a python convention for when you should implement __str__() versus __unicode__() . I've seen classes override __unicode__() more frequently than __str__() but it doesn't appear to be consistent. Are there specific rules when it is better to implement one versus the other? Is it ne...
C++ preprocessor __VA_ARGS__ number of arguments
...re however you have a macro implementation that does the count:
#define PP_NARG(...) \
PP_NARG_(__VA_ARGS__,PP_RSEQ_N())
#define PP_NARG_(...) \
PP_ARG_N(__VA_ARGS__)
#define PP_ARG_N( \
_1, _2, _3, _4, _5, _6, _7, _8, _9,_10, \
_11,_12,_13,_14,_15,_16,_17,_18,_...
What is the most efficient/elegant way to parse a flat table into a tree?
...e Pitfalls of Database Programming.
CREATE TABLE ClosureTable (
ancestor_id INT NOT NULL REFERENCES FlatTable(id),
descendant_id INT NOT NULL REFERENCES FlatTable(id),
PRIMARY KEY (ancestor_id, descendant_id)
);
Store all paths in the Closure Table, where there is a direct ancestry from o...
Python extending with - using super() Python 3 vs Python 2
...
super() (without arguments) was introduced in Python 3 (along with __class__):
super() -> same as super(__class__, self)
so that would be the Python 2 equivalent for new-style classes:
super(CurrentClass, self)
for old-style classes you can always use:
class Classname(OldStyleParen...
What are “first class” objects?
...ally has a fairly rich and sophisticated interface.
>>> dir(2)
['__abs__', '__add__', '__and__', '__class__', '__cmp__', '__coerce__', '__delattr__', '__div__', '__divmod__', '__doc__', '__float__', '__floordiv__', '__getattribute__', '__getnewargs__', '__hash__', '__hex__', '__index__', '...
How to properly assert that an exception gets raised in pytest?
...
pytest.raises(Exception) is what you need.
Code
import pytest
def test_passes():
with pytest.raises(Exception) as e_info:
x = 1 / 0
def test_passes_without_info():
with pytest.raises(Exception):
x = 1 / 0
def test_fails():
with pytest.raises(Exception) as e_info:
...
How to print to console in pytest?
...as printed to standard out in that particular test.
For example,
def test_good():
for i in range(1000):
print(i)
def test_bad():
print('this should fail!')
assert False
Results in the following output:
>>> py.test tmp.py
============================= test session s...
Build an ASCII chart of the most commonly used words in a given text [closed]
...$<.read.downcase.scan(/[a-z]+/)-%w{the and of to a i it in or is}).group_by{|x|x}.map{|x,y|[-y.size,x]}.sort[0,22]
k,l=w[0]
puts [?\s+?_*m=76-l.size,w.map{|f,x|?|+?_*(f*m/k)+"| "+x}]
Instead of using any command line switches like the other solutions, you can simply pass the filename as argumen...
How do I achieve the theoretical maximum of 4 FLOPs per cycle?
...m>
using namespace std;
typedef unsigned long long uint64;
double test_dp_mac_SSE(double x,double y,uint64 iterations){
register __m128d r0,r1,r2,r3,r4,r5,r6,r7,r8,r9,rA,rB,rC,rD,rE,rF;
// Generate starting data.
r0 = _mm_set1_pd(x);
r1 = _mm_set1_pd(y);
r8 = _mm_set1_pd(...