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In C#, why is String a reference type that behaves like a value type?
...tance, an Int32 is always 4 bytes, thus the compiler allocates 4 bytes any time you define a string variable. How much memory should the compiler allocate when it encounters an int variable (if it were a value type)? Understand that the value has not been assigned yet at that time.
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How do I output text without a newline in PowerShell?
...on, available from PowerShell 3.0 onward, see manual for details.
# Total time to sleep
$start_sleep = 120
# Time to sleep between each notification
$sleep_iteration = 30
Write-Output ( "Sleeping {0} seconds ... " -f ($start_sleep) )
for ($i=1 ; $i -le ([int]$start_sleep/$sleep_iteration) ; $i++)...
Parsing huge logfiles in Node.js - read in line-by-line
... readline module is a pain. It does not pause and was causing failure everytime after 40-50 million. Wasted a day. Thanks a lot for the answer. This one works perfectly
– Mandeep Singh
Jun 7 '16 at 17:42
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How to Validate a DateTime in C#?
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DateTime.TryParse
This I believe is faster and it means you dont have to use ugly try/catches :)
e.g
DateTime temp;
if(DateTime.TryParse(startDateTextBox.Text, out temp))
{
// Yay :)
}
else
{
// Aww.. :(
}
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Remove columns from dataframe where ALL values are NA
...ect the same size as df.
Here are two approaches that are more memory and time efficient
An approach using Filter
Filter(function(x)!all(is.na(x)), df)
and an approach using data.table (for general time and memory efficiency)
library(data.table)
DT <- as.data.table(df)
DT[,which(unlist(lapp...
Random alpha-numeric string in JavaScript? [duplicate]
... seems to have some problems. As you can see from THIS screenshot, it sometimes generates strings that aren't the specified length. I put your randomString(..) function in a for(var i=0;i<50;i++){} loop that generated 50 random strings, and the last one is three characters long. I also told it...
How can I use map and receive an index as well in Scala?
...
Or, assuming your collection has constant access time, you could map the list of indexes instead of the actual collection:
val ls = List("a","b","c")
0.until(ls.length).map( i => doStuffWithElem(i,ls(i)) )
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How can I split a JavaScript string by white space or comma?
...y should have tested it before I made that last edit. I have now, and this time it really should work.
– KaptajnKold
Mar 22 '13 at 12:50
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I have 2 dates in PHP, how can I run a foreach loop to go through all of those days?
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Requires PHP5.3:
$begin = new DateTime('2010-05-01');
$end = new DateTime('2010-05-10');
$interval = DateInterval::createFromDateString('1 day');
$period = new DatePeriod($begin, $interval, $end);
foreach ($period as $dt) {
echo $dt->format("l Y-m-d ...
Why is the .bss segment required?
...lized variables? If an uninitialised variable has a value assigned at run time, does the variable exist still in the .bss segment only?
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