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How do I compute derivative using Numpy?
...ivatives by hand.
Finite differences require no external tools but are prone to numerical error and, if you're in a multivariate situation, can take a while.
Symbolic differentiation is ideal if your problem is simple enough. Symbolic methods are getting quite robust these days. SymPy is an exce...
Scroll to bottom of Div on page load (jQuery)
...
Well done! I was looking for a snippet to scroll and all I could find it page scrolling (html, body). This is a great solution and using scrollHeight is a great way to make sure it always reaches the bottom.
–...
Java Reflection: How to get the name of a variable?
...date" section below.
Complete information is often stored in class files. One compile-time optimization is to remove it, saving space (and providing some obsfuscation). However, when it is is present, each method has a local variable table attribute that lists the type and name of local variables, ...
Objective-C: Reading a file line by line
...(large size of text), then use the method that other people here were mentioned such as buffered (reserve the size of the text in memory space).
Say you read a Text File.
NSString* filePath = @""//file path...
NSString* fileRoot = [[NSBundle mainBundle]
pathForResource:filePath ofT...
Optional Methods in Java Interface
...contain the remove operation.
Now can you do away with UnsupportedOperationException? Unfortunately
not.
Consider arrays. They implement most of the List operations, but not
remove and add. They are "fixed-size" Lists. If you want to capture
this notion in the hierarchy, you have to add...
Delete all records in a table of MYSQL in phpMyAdmin
...o delete all records of a table in phpMyAdmin (select all) it deletes only one record not all records. Why it does not delete all records?
...
Why Doesn't C# Allow Static Methods to Implement an Interface?
...ke a non-nullable “this” argument (unlike an instance or virtual), but one where the method called would depend on the constructed type of T (unlike a static, which must be determinable at compile time).
but is yet to be convinced of its usefulness.
...
What is the easiest way to duplicate an activerecord record?
...
To get a copy, use the clone (or dup for rails 3.1+) method:
# rails < 3.1
new_record = old_record.clone
#rails >= 3.1
new_record = old_record.dup
Then you can change whichever fields you want.
ActiveRecord overrides the built-in Object#cl...
Why not infer template parameter from constructor?
...genuinely can't believe it was accepted, reached +29, took 6 years for someone to notice the glaring problem, and sat without a single downvote for 7 years. Does no one else think while they read, or...?
– underscore_d
Aug 21 '16 at 19:19
...
How to write a scalable Tcp/Ip based server
...catch (System.Net.Sockets.SocketException e)
{
throw new ApplicationException("Could not create socket, check to make sure not duplicating port", e);
}
try
{
_serverSocket.Bind(serverEndPoint);
_serverSocket.Listen(_backlog);
}
catch (Exception e)
{
...