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How do you create nested dict in Python?
...he following:
d = {} # can use defaultdict(dict) instead
for row in file_map:
# derive row key from something
# when using defaultdict, we can skip the next step creating a dictionary on row_key
d[row_key] = {}
for idx, col in enumerate(row):
d[row_key][idx] = col
Ac...
Getting the name of a child class in the parent class (static context)
...ot possible. in php4 you could implement a terrible hack (examine the debug_backtrace()) but that method does not work in PHP5. references:
30423
37684
34421
edit: an example of late static binding in PHP 5.3 (mentioned in comments). note there are potential problems in it's current implementat...
C++中判断文件、目录是否存在的几种方法 - C/C++ - 清泛网 - 专注C/C++及内核技术
...
if(fh == NULL)
{
printf("%s","can not open the file");
}
三、_access
当然C中还有一种方式是直接调用c的函数库。
就是函数 int _access(const char* path,int mode);
这个函数的功能十分强大。
可以看看msdn的详细介绍
#include <io.h>
#include ...
How to call a Parent Class's method from Child Class in Python?
...P was asking how to do it without explicitly naming the superclass at the call site (Bar, in this case).
– Adam Rosenfield
Apr 30 '09 at 2:13
8
...
Android Preferences: How to load the default values when the user hasn't used the preferences-screen
...means this will only set the default values if this method has never been called in the past so you don't need to worry about overriding the user's settings each time your Activity is created
Take a look into PreferenceManager.setDefaultValues in Android API for further investigation.
...
What is the fastest way to create a checksum for large files in C#
...me machines. The files can be up to 6GB in size. The sync will be done manually every few weeks. I cant take the filename into consideration because they can change anytime.
...
What's the difference between eval, exec, and compile?
...
The short answer, or TL;DR
Basically, eval is used to evaluate a single dynamically generated Python expression, and exec is used to execute dynamically generated Python code only for its side effects.
eval and exec have these two differences:
eval accep...
Change drawable color programmatically
...
How to remove it programatically ?
– Hardik Joshi
Oct 4 '18 at 9:04
1
...
Why does Go have a “goto” statement
... x = x + 1
}
if x == 2 {
return z
}
x = x - 2
p = (((((x*_gamP[0]+_gamP[1])*x+_gamP[2])*x+_gamP[3])*x+_gamP[4])*x+_gamP[5])*x + _gamP[6]
q = ((((((x*_gamQ[0]+_gamQ[1])*x+_gamQ[2])*x+_gamQ[3])*x+_gamQ[4])*x+_gamQ[5])*x+_gamQ[6])*x + _gamQ[7]
return z * p / q
small:
if x == 0 ...
How to extract the year from a Python datetime object?
...ew times and you'll be prompted with the members of the "now" object:
now.__add__ now.__gt__ now.__radd__ now.__sub__ now.fromordinal now.microsecond now.second now.toordinal now.weekday
now.__class__ now.__hash__ ...