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What is the C# equivalent of NaN or IsNumeric?
What is the most efficient way of testing an input string whether it contains a numeric value (or conversely Not A Number)? I guess I can use Double.Parse or a regex (see below) but I was wondering if there is some built in way to do this, such as javascript's NaN() or IsNumeric() (was that VB...
Difference between del, remove and pop on lists
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@rite2hhh it tests for equality. Equality tests test for identity first as an optimisation
– Martijn Pieters♦
Dec 26 '19 at 20:33
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Which method performs better: .Any() vs .Count() > 0?
...n<T>, IList<T>, List<T>, etc) - then this will be the fastest option, since it doesn't need to go through the GetEnumerator()/MoveNext()/Dispose() sequence required by Any() to check for a non-empty IEnumerable<T> sequence.
For just IEnumerable<T>, then Any() will gene...
Loop through files in a folder using VBA?
... takes wild cards so you could make a big difference adding the filter for test up front and avoiding testing each file
Sub LoopThroughFiles()
Dim StrFile As String
StrFile = Dir("c:\testfolder\*test*")
Do While Len(StrFile) > 0
Debug.Print StrFile
StrFile = Dir
L...
Read String line by line
...ce I was especially interested in the efficiency angle, I created a little test class (below). Outcome for 5,000,000 lines:
Comparing line breaking performance of different solutions
Testing 5000000 lines
Split (all): 14665 ms
Split (CR only): 3752 ms
Scanner: 10005
Reader: 2060
As usual, exact t...
What is a lambda (function)?
...an primitive type.
Predicate<Integer> pred = x -> x % 2 == 0; // Tests if the parameter is even.
boolean result = pred.test(4); // true
Lua
adder = function(x)
return function(y)
return x + y
end
end
add5 = adder(5)
add5(1) == 6 -- true
Kotlin
val pred = { x: I...
Controlling mouse with Python
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Tested on WinXP, Python 2.6 (3.x also tested) after installing pywin32 (pywin32-214.win32-py2.6.exe in my case):
import win32api, win32con
def click(x,y):
win32api.SetCursorPos((x,y))
win32api.mouse_event(win32con.MO...
In JavaScript can I make a “click” event fire programmatically for a file input element?
...t have the time to work my way through all 10+ flavors of relevant ones to test on.
– Yevgeny Simkin
Sep 15 '10 at 5:11
1
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Check for null in foreach loop
...> in the answer you link to. Which have the same performance penalty of testing whether the enumerable is null.
– Rune FS
May 3 '19 at 9:36
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string.split - by multiple character delimiter
...th characters right? What if I want to split by either "[" or "]"? From my tests so far I guess thats a different story, right?
– C4d
Mar 7 '16 at 15:28
3
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