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Pandas percentage of total with groupby
... is a table of some kind, so 100 * x doesn't intuitively make sense (especially when some of the cells contain strings like AZ, ...).
– dhardy
Feb 6 '15 at 9:42
6
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Is it possible to ping a server from Javascript?
...ther parts of the source but you get the idea).
function Pinger_ping(ip, callback) {
if(!this.inUse) {
this.inUse = true;
this.callback = callback
this.ip = ip;
var _that = this;
this.img = new Image();
this.img.onload = function() {_that.good();};
this.img.onerro...
error C2780: \'void __cdecl std::sort(_RI,_RI,_Pr)\' : expects 3 argum...
error C2780: 'void __cdecl std::sort(_RI,_RI,_Pr)' : expects 3 arguments - 2 providedprog7.cpp(8) :error C2780:'void __cdecl std::sort(_RI,_RI,_Pr)' : expects 3 arguments - 2 provided C: Pr...prog7.cpp(8) : error C2780: 'void __cdecl std::sort(_RI,_RI,_Pr)' : expects 3 arguments - 2 provided
C:...
使用std::string作为std::map的key出错解决 - C/C++ - 清泛网 - 专注C/C++及内核技术
...0\vc\include\xstddef(180): error C2784: “bool std::operator <(const std::_Tree<_Traits> &,const std::_Tree<_Traits> &)”: 未能从“const std::string”为“const std::_Tree<_Traits> &”推导 模板 参数
1> c:\program files (x86)\microsoft visual studio 11.0\vc\include\xtree(2245...
How to change field name in Django REST Framework
...get_alternate_name(self, obj):
return obj.alternate_name
Additionally, you can use serializers.CharField with source attribute:
class ParkSerializer(serializers.ModelSerializer):
location = serializers.CharField(source='other_fields')
class Meta:
model = Park
fiel...
How to generate a random number in C++?
...
The most fundamental problem of your test application is that you call srand once and then call rand one time and exit.
The whole point of srand function is to initialize the sequence of pseudo-random numbers with a random seed.
It means that if you pass the same value to srand in two differ...
Read only file system on Android
...
Not all phones and versions of android have things mounted the same.
Limiting options when remounting would be best.
Simply remount as rw (Read/Write):
# mount -o rw,remount /system
Once you are done making changes, remount t...
Two-way encryption: I need to store passwords that can be retrieved
...
Personally, I would use mcrypt like others posted. But there is much more to note...
How do I encrypt and decrypt a password in PHP?
See below for a strong class that takes care of everything for you:
What is the safest algorit...
STL：accumulate与自定义数据类型 - C/C++ - 清泛网 - 专注C/C++及内核技术
...mulate()的原型为(文件取自DEV-C++编译器)：
template<typename _InputIterator, typename _Tp, typename _BinaryOperation>
_Tp accumulate(_InputIterator __first, _InputIterator __last, _Tp __init,
_BinaryOperation __binary_op)
{
// concept requirements
__glibcxx...
What kind of leaks does automatic reference counting in Objective-C not prevent or minimize?
... platforms, memory leaks are often caused by unreleased pointers. Traditionally, it has always been of utmost importance to check your allocs, copies and retains to make sure each has a corresponding release message.
...