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Trimming a huge (3.5 GB) csv file to read into R
... expert at this, but you might consider trying MapReduce, which would basically mean taking a "divide and conquer" approach. R has several options for this, including:
mapReduce (pure R)
RHIPE (which uses Hadoop); see example 6.2.2 in the documentation for an example of subsetting files
Alterna...
How to generate all permutations of a list?
How do you generate all the permutations of a list in Python, independently of the type of elements in that list?
33 Answer...
std::shared_ptr thread safety explained
...ly regarding your original 3 questions.
But the ending part of your edit
Calling reset() in thread IV will delete previous instance of A class created in first thread and replace it with new instance? Moreover after calling reset() in IV thread other threads will see only newly created object?
is ...
Using multiple delimiters in awk
...n the input field separator.
See another example:
$ cat file
hello#how_are_you
i#am_very#well_thank#you
This file has two fields separators, # and _. If we want to print the second field regardless of the separator being one or the other, let's make both be separators!
$ awk -F"#|_" '{print ...
Location Services not working in iOS 8
... check whether the user is running iOS 8 or iOS 7. For example:
#define IS_OS_8_OR_LATER ([[[UIDevice currentDevice] systemVersion] floatValue] >= 8.0)
//In ViewDidLoad
if(IS_OS_8_OR_LATER) {
[self.locationManager requestAlwaysAuthorization];
}
[self.locationManager startUpdatingLocation];
...
What is the difference between Cygwin and MinGW?
...Unix-based applications to Windows much easier, by emulating many of the small details that Unix-based operating systems provide, and are documented by the POSIX standards. Your application can use Unix feature such as pipes, Unix-style file and directory access, and so forth, and it can be compile...
map function for objects (instead of arrays)
... of obj1 sit on the 'prototype' of obj2
console.log(obj2) // Prints: obj2.__proto__ = { 'a': 1, 'b': 2, 'c': 3}
console.log(Object.keys(obj2)); // Prints: an empty Array.
for (key in obj2) {
console.log(key); // Prints: 'a', 'b', 'c'
}
jsbin
However, please do me a favor and av...
How to set cornerRadius for only top-left and top-right corner of a UIView?
...WillLayoutSubviews() {
super.viewWillLayoutSubviews()
// Call the roundCorners() func right there.
theView.roundCorners(corners: [.topLeft, .topRight], radius: 30)
}
}
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windows C++ gbk转为utf-8 - C/C++ - 清泛网 - 专注C/C++及内核技术
...码转换为linux使用的utf8格式的，否则会出现乱码。
//m_string是windows下的中文字符串
//utf8_string是返回转换为utf8编码的中文字符串
//slen是utf8_string字符数组的大小
int multichar_2_utf8(const char *m_string,char *utf8_string,int slen) {
int le...
Android存储系统基础知识：内部存储，外部存储，App特定目录 ASD(app speci...
...r
file:///storage/emulated/0/
要访问外部存储，需要 READ_ 或 WRITE_EXTERNAL_STORAGE 权限。
App特定目录 ASD(App-specific directory)
此外，可能还有一个特定于应用程序的目录（ASD），可以使用以下命令创建
Tai...