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NSUserDefaults removeObjectForKey vs. setObject:nil
...m not positive.
To completely remove a value for a key use UserDefaults.standard.removeObject(forKey: "YourDefault")
I tested with the following code:
UserDefaults.standard.set(["a", "b", "c"], forKey: "MyDefaults")
print("Test A: My saved defaults \(UserDefaults.standard.object(forKey: "MyDefaul...
How to smooth a curve in the right way?
...ter of the window. Finally the window is shifted forward by one data point and the process repeats. This continues until every point has been optimally adjusted relative to its neighbors. It works great even with noisy samples from non-periodic and non-linear sources.
Here is a thorough cookbook ex...
Is it possible to get element from HashMap by its position?
...
Use a LinkedHashMap and when you need to retrieve by position, convert the values into an ArrayList.
LinkedHashMap<String,String> linkedHashMap = new LinkedHashMap<String,String>();
/* Populate */
linkedHashMap.put("key0","value0");...
boost多索引容器multi_index_container实战 - C/C++ - 清泛网 - 专注C/C++及内核技术
boost多索引容器multi_index_container实战boost多索引容器multi_index_container用法详解、性能测试等。目录：
boost多索引容器multi_index_container详解
boost多索引容器multi_index_container架构图
boost多索引容器multi_index_container性能测试
原文地...
Should I make HTML Anchors with 'name' or 'id'?
...cation, 5.9.8 Navigating to a fragment identifier:
For HTML documents (and the text/html MIME type), the following processing model must be followed to determine what the indicated part of the document is.
Parse the URL, and let fragid be the <fragment> component of the URL.
...
How to redirect to a 404 in Rails?
...
raise ActionController::RoutingError.new('Not Found')
end
Rails also handles AbstractController::ActionNotFound, and ActiveRecord::RecordNotFound the same way.
This does two things better:
1) It uses Rails' built in rescue_from handler to render the 404 page, and
2) it interrupts the executi...
Count occurrences of a char in a string using Bash
...
I would use the following awk command:
string="text,text,text,text"
char=","
awk -F"${char}" '{print NF-1}' <<< "${string}"
I'm splitting the string by $char and print the number of resulting fields minus 1.
If your shell does not support the <...
Mechanisms for tracking DB schema changes [closed]
What are the best methods for tracking and/or automating DB schema changes? Our team uses Subversion for version control and we've been able to automate some of our tasks this way (pushing builds up to a staging server, deploying tested code to a production server) but we're still doing database up...
How to modify a text file?
I'm using Python, and would like to insert a string into a text file without deleting or copying the file. How can I do that?
...
Analyze audio using Fast Fourier Transform
...you need to calculate the square root of the sum of the square of its real and imaginary components. That is, if your coefficient is a + b*j, then its magnitude is sqrt(a^2 + b^2).
Once you have calculated the magnitude of each FFT coefficient, you need to figure out which audio frequency each FFT ...