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Padding characters in printf
...E has spaces unless they are already escaped. You'll get one line with two tokens each and then [UP] for every two space-separated tokens in your variable and then a single line at the end with your line text minus the total length of your input string. So be careful, since this could lead to intere...
What does immutable mean?
...ed in will not be modified. Once you create a string "foo", some memory is allocated to store the value "foo". This memory will not be altered. If you modify the string with, say, substr(1), a new string is created and a different part of memory is allocated which will store "oo". Now you have two s...
If Python is interpreted, what are .pyc files?
... form (or near source, a form in which keywords were represented by 1-byte tokens, and line #'s by 2-byte binary ints, but the rest was just ASCII). So in fact a 'goto' would take different amounts of time depending on how many source lines it had to search through looking for the matching destinati...
When to catch java.lang.Error?
...in multithreaded applications, or is there a significant risk that smaller allocations in other threads fail because of it? … presumably only if your arrays were just small enough to be allocated, but left nothing for anyone else.
– PJTraill
Jun 11 '15 at 14:...
How to solve error “Missing `secret_key_base` for 'production' environment” (Rails 4.1)
...oduce this is beyond the scope of this answer but the TL;DR is that secret_token.rb conflates configuration and code as well as being a security risk since the token is checked into source control history and the only system that needs to know the production secret token is the production infrastruc...
Append value to empty vector in R?
... avoided".
As BrodieG mentioned in the comments: it is much better to pre-allocate a vector of the desired length, then set the element values in the loop.
Here are several ways to append values to a vector. All of them are discouraged.
Appending to a vector in a loop
# one way
for (i in 1:le...
Advantages of Binary Search Trees over Hash Tables
... instance, if a hash function has a range R(h) = 0...100, then you need to allocate an array of 100 (pointers-to) elements, even if you are just hashing 20 elements. If you were to use a binary search tree to store the same information, you would only allocate as much space as you needed, as well as...
实战Nginx与PHP（FastCGI）的安装、配置与优化 - 更多技术 - 清泛网 - 专注...
实战Nginx与PHP（FastCGI）的安装、配置与优化一篇介绍nginx和php-fmp配置，安装和使用的博文，文章将为何将nginx叫做反向代理服务器讲明白了，也能从中看出为什么ngnix会apache性能更加...一篇介绍nginx和php-fmp配置，安装和使用的博...
Applying .gitignore to committed files
...-ci --exclude-standard -z | xargs -0 git rm --cached
//On Windows:
for /F "tokens=*" %a in ('git ls-files -ci --exclude-standard') do @git rm --cached "%a"
//On mac
alias apply-gitignore="git ls-files -ci --exclude-standard -z | xargs -0 git rm --cached"
to remove them from the repository (without...
Is there a documented way to set the iPhone orientation?
...ish to use undocumented methods:
UIViewController *c = [[UIViewController alloc]init];
[self presentModalViewController:c animated:NO];
[self dismissModalViewControllerAnimated:NO];
[c release];
It is sufficient to present and dismiss a vanilla view controller.
Obviously you'll still need to con...