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How can I get a precise time, for example in milliseconds in Objective-C?
...meInterval is in seconds, but it uses the double to give you greater precision.
In order to calculate millisecond time accuracy, you can do:
// Get a current time for where you want to start measuring from
NSDate *date = [NSDate date];
// do work...
// Find elapsed time and convert to millisecon...
How to Deal with Temporary NSManagedObject instances?
...OTE: This answer is very old. See comments for full history. My recommendation has since changed and I no longer recommend using unassociated NSManagedObject instances. My current recommendation is to use temporary child NSManagedObjectContext instances.
Original Answer
The easiest way to do this ...
When is the thread pool used?
...derstanding of how node works isn't correct... but it's a common misconception, because the reality of the situation is actually fairly complex, and typically boiled down to pithy little phrases like "node is single threaded" that over-simplify things.
For the moment, we'll ignore explicit multi-pr...
Reading large text files with streams in C#
...ask of working out how to handle large files being loaded into our application's script editor (it's like VBA for our internal product for quick macros). Most files are about 300-400 KB which is fine loading. But when they go beyond 100 MB the process has a hard time (as you'd expect).
...
How to read a .xlsx file using the pandas Library in iPython?
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I usually create a dictionary containing a DataFrame for every sheet:
xl_file = pd.ExcelFile(file_name)
dfs = {sheet_name: xl_file.parse(sheet_name)
for sheet_name in xl_file.sheet_names}
Update: In pandas version 0.21.0+ you will ...
How to access test resources in Scala?
...ME/src/test/resources/, you can access it in a test like so:
import scala.io.Source
// The string argument given to getResource is a path relative to
// the resources directory.
val source = Source.fromURL(getClass.getResource("/data.xml"))
Of course that source is now just a normal Scala IO obj...
How do I create directory if it doesn't exist to create a file?
... to the file.
....Or, If it exists, then create (else do nothing)
System.IO.FileInfo file = new System.IO.FileInfo(filePath);
file.Directory.Create(); // If the directory already exists, this method does nothing.
System.IO.File.WriteAllText(file.FullName, content);
...
Read properties file outside JAR file
...her than as a resource of the main/runnable jar. In that case, my own solution is as follows:
First thing first: your program file architecture shall be like this (assuming your main program is main.jar and its main properties file is main.properties):
./ - the root of your program
|__ main.jar
...
Convert NSArray to NSString in Objective-C
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NSString * result = [[array valueForKey:@"description"] componentsJoinedByString:@""];
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How do I animate constraint changes?
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Two important notes:
You need to call layoutIfNeeded within the animation block. Apple actually recommends you call it once before the animation block to ensure that all pending layout operations have been completed
You need to call it specifically on the parent view (e.g. self.view), not th...