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When to use .First and when to use .FirstOrDefault with LINQ?
I've searched around and haven't really found a clear answer as to when you'd want to use .First and when you'd want to use .FirstOrDefault with LINQ.
...
float64 with pandas to_csv
...mvent this problem, I recommend you create another CSV file which contains all figures as integers, for example multiplying by 100, 1000 or other factor which turns out to be convenient. Inside your application, read the CSV file as usual and you will get those integer figures back. Then convert tho...
Why is extending native objects a bad practice?
...ody does it "the wrong way", and adds enumerable types to Object , practically destroying all loops on any object?
8 Answe...
Why does Javascript's regex.exec() not always return the same value? [duplicate]
... matches by performing the assignment as the loop condition.
var re = /foo_(\d+)/g,
str = "text foo_123 more text foo_456 foo_789 end text",
match,
results = [];
while (match = re.exec(str))
results.push(+match[1]);
DEMO: http://jsfiddle.net/pPW8Y/
If you don't like the placem...
Getting key with maximum value in dictionary?
...
@oba2311 max_value = max(stats.values()); {key for key, value in stats.items() if value == max_value}
– A. Coady
Apr 4 '17 at 0:37
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Correct way to close nested streams and writers in Java [duplicate]
...
I usually do the following. First, define a template-method based class to deal with the try/catch mess
import java.io.Closeable;
import java.io.IOException;
import java.util.LinkedList;
import java.util.List;
public abstract cl...
Regular expression for first and last name
... I would escape the special characters in these regexps - especially . (decimal point/dot/full stop) since it's the regexp wildcard =)
– Joel Purra
Aug 8 '12 at 18:45
32...
What is the difference between lock and Mutex?
...hine.
bool firstInstance;
Mutex mutex = new Mutex(false, @"Local\DASHBOARD_MAIN_APPLICATION", out firstInstance);
if (!firstInstance)
{
//another copy of this application running
}
else
{
//run main application loop here.
}
// Refer to the mutex down here so garbage collection doesn't chu...
Difference between method and function in Scala
..., no instance - with a method type. As mentioned above, a Method Value actually has a Function Type. A method type is a def declaration - everything about a def except its body.
Value Declarations and Definitions and Variable Declarations and Definitions are val and var declarations, including both...
Visual Studio immediate window command for Clear All
... you can use >cls, which is a predefined command alias to >Edit.ClearAll.
The MSDN article lists all predefined aliases and you can define your own, too. (For VS 2010 and earlier, custom aliases are described in a separate article, though.) Scanning through, there's a whole slew of them, some...