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Using Python String Formatting with Lists
...ruct a string s in Python 2.6.5 which will have a varying number of %s tokens, which match the number of entries in list x . I need to write out a formatted string. The following doesn't work, but indicates what I'm trying to do. In this example, there are three %s tokens and the list has thr...
Difference in make_shared and normal shared_ptr in C++
...
The difference is that std::make_shared performs one heap-allocation, whereas calling the std::shared_ptr constructor performs two.
Where do the heap-allocations happen?
std::shared_ptr manages two entities:
the control block (stores meta data such as ref-counts, type-erased del...
Why should I use a pointer rather than the object itself?
...
It's very unfortunate that you see dynamic allocation so often. That just shows how many bad C++ programmers there are.
In a sense, you have two questions bundled up into one. The first is when should we use dynamic allocation (using new)? The second is when should w...
Get path of executable
...t;boost/predef.h>
#include <boost/version.hpp>
#include <boost/tokenizer.hpp>
#if (BOOST_VERSION > BOOST_VERSION_NUMBER(1,64,0))
# include <boost/process.hpp>
#endif
#if (BOOST_OS_CYGWIN || BOOST_OS_WINDOWS)
# include <Windows.h>
#endif
#include <boost/executabl...
How to add 2 buttons into the UINavigationbar on the right side without IB?
...ith iOS 5+ it's as easy as:
UIBarButtonItem *btnShare = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemAction target:self action:@selector(share)];
UIBarButtonItem *btnRefresh = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemRefresh target:self ...
Do threads have a distinct heap?
... a stack overflow.
Since all threads share the same heap, access to the allocator/deallocator must be synchronized. There are various methods and libraries for avoiding allocator contention.
Some languages allow you to create private pools of memory, or individual heaps, which you can assign ...
Choice between vector::resize() and vector::reserve()
I am pre-allocating some memory to my a vector member variable. Below code is minimal part
4 Answers
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What is the difference between Google App Engine and Google Compute Engine?
...e docker to install s/w in GAE, does it mean google takes care of creating/allocating a linux instance with basic configurations and then runs docker on tops of it? In essence, compute engine adds additional responsibility of VM configs. Am I right?
– old-monk
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How to extract a floating number from a string [duplicate]
...at by stepping to it directly:
user_input = "Current Level: 1e100 db"
for token in user_input.split():
try:
# if this succeeds, you have your (first) float
print float(token), "is a float"
except ValueError:
print token, "is something else"
# => Would print ...
#...
How can I match on an attribute that contains a certain string?
...g with a trick to ensure the comparison is done at the level of a complete token (lest the 'atag' pattern be found as part of another 'tag').
"atag btag" is an odd value for the class attribute, but never the less, try:
//*[starts-with(@class,"atag")]
...