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C# 'is' operator performance
...ClassTypeEnum { A, B }
public ClassTypeEnum ClassType { get; protected set; }
}
class MyClassA : MyBaseClass
{
public MyClassA()
{
ClassType = MyBaseClass.ClassTypeEnum.A;
}
}
class MyClassB : MyBaseClass
{
public MyClassB()
{
ClassType = MyBaseClass.ClassTyp...
Asynchronously wait for Task to complete with timeout
I want to wait for a Task<T> to complete with some special rules:
If it hasn't completed after X milliseconds, I want to display a message to the user.
And if it hasn't completed after Y milliseconds, I want to automatically request cancellation .
...
Execute a terminal command from a Cocoa app
... There's a small glitch in your answer. NSPipe has a buffer (set at the OS level), which is flushed when it's read. If the buffer fills up, NSTask will hang, and your app will hang too, indefinitely. No error message will appear. This can happen if the NSTask returns a lot of info. The...
Changing password with Oracle SQL Developer
...
SQL Developer has a built-in reset password option that may work for your situation. It requires adding Oracle Instant Client to the workstation as well. When instant client is in the path when SQL developer launches you will get the following option ena...
How to get users to read error messages?
If you program for a nontechnical audience, you find yourself at a high risk that users will not read your carefully worded and enlightening error messages, but just click on the first button available with a shrug of frustration.
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++someVariable vs. someVariable++ in JavaScript
... editor after snippets, if snippets enabled
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Rails: How can I set default values in ActiveRecord?
How can I set default value in ActiveRecord?
27 Answers
27
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How to reshape data from long to wide format
... the terms for melt/cast.
Edit: Now, in 2019, tidyr v 1.0 has launched and set spread and gather on a deprecation path, preferring instead pivot_wider and pivot_longer, which you can find described in this answer. Read on if you want a brief glimpse into the brief life of spread/gather.
library(tidy...
Multiple linear regression in Python
I can't seem to find any python libraries that do multiple regression. The only things I find only do simple regression. I need to regress my dependent variable (y) against several independent variables (x1, x2, x3, etc.).
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Class with single method — best approach?
...ng in the required parameters in the constructor, and allowing the user to set optional values through properties, or methods to set multiple interdependent values at the same time. Also, if a method has grown to this amount of complexity, it most likely needs to be in its own class anyways.
Demand...