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How can I use map and receive an index as well in Scala?
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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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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...
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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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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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 ...
Intellij reformat on file save
... You will have to check the box "Do not show this message again" the first time for the organized imports, but it works as expected after that.
Step-by-step for IntelliJ 10.0:
Code -> "Optimize Imports...", if a dialogue box appears, check the box that says "Do not show this message again.", t...
How do I check if a string is unicode or ascii?
... unicode):
s = str(s)
Those are both unpythonic, and most of the time there's probably a better way.
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Comparison of Android networking libraries: OkHTTP, Retrofit, and Volley [closed]
...Vutukuri: You are commenting on an answer from over two years ago. At that time, there was no documentation.
– CommonsWare
Sep 8 '16 at 10:56
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How to create cron job using PHP?
...llowing in the linux/ubuntu terminal
crontab -e
select an editor (sometime it asks for the editor)
and this to run for every minute
* * * * * /usr/bin/php path/to/cron.php &> /dev/null
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Using multiple delimiters in awk
...r # or a space, where the separating character must be repeated at least 2 times and not more than 6 times, for example:
awk -F'[2-5a# ]{2,6}' ...
I am sure variations of this exist using ( ) and parameters
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