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System.Threading.Timer in C# it seems to be not working. It runs very fast every 3 second
I've a timer object. I want it to be run every minute. Specifically, it should run a OnCallBack method and gets inactive while a OnCallBack method is running. Once a OnCallBack method finishes, it (a OnCallBack ) restarts a timer.
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Convert a list of data frames into one data frame
...mes, data.frame)
This is a little slower than the original:
> system.time({ df <- do.call("rbind", listOfDataFrames) })
user system elapsed
0.25 0.00 0.25
> system.time({ df2 <- ldply(listOfDataFrames, data.frame) })
user system elapsed
0.30 0.00 0.29
>...
Link to add to Google calendar
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Note you can also specify a time zone parameter e.g.: ctz=America/New_York
– User
Feb 28 '14 at 15:27
25
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Type Checking: typeof, GetType, or is?
...ll are different.
typeof takes a type name (which you specify at compile time).
GetType gets the runtime type of an instance.
is returns true if an instance is in the inheritance tree.
Example
class Animal { }
class Dog : Animal { }
void PrintTypes(Animal a) {
Console.WriteLine(a.GetType...
Constants in Objective-C
I'm developing a Cocoa application, and I'm using constant NSString s as ways to store key names for my preferences.
14 ...
iphone ios running in separate thread
What is the best way to run code on a separate thread? Is it:
4 Answers
4
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z-index not working with position absolute
I opened the console (chrome\firefox) and ran the following lines:
5 Answers
5
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Static/Dynamic vs Strong/Weak
...namic Typing is about when type information is acquired (Either at compile time or at runtime)
Strong/Weak Typing is about how strictly types are distinguished (e.g. whether the language tries to do an implicit conversion from strings to numbers).
See the wiki-page for more detailed information.
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How do I get my C# program to sleep for 50 msec?
...y programming language:
Loose waiting
Executing thread blocks for given time (= does not consume processing power)
No processing is possible on blocked/waiting thread
Not so precise
Tight waiting (also called tight loop)
processor is VERY busy for the entire waiting interval (in fact, it usuall...
What is Lazy Loading?
...ople might use lazy loading, consider an application that takes a LOOOOONG time to start. This application is probably doing a lot of eager loading... loading things from disk, and doing calculations and whatnot long before it is ever needed.
Compare this to lazy loading, the application would sta...