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Bash conditionals: how to “and” expressions? (if [ ! -z $VAR && -e $VAR ])
...te easily handle empty strings. If that's what you want then you don't actually need the -z non-empty check:
pax> VAR=xyzzy
pax> if [[ -e $VAR ]] ; then echo yes ; fi
pax> VAR=/tmp
pax> if [[ -e $VAR ]] ; then echo yes ; fi
yes
In other words, just use:
if [[ -e "$var" ]] ; then
...
Github: Import upstream branch into fork
...etween the branch in the upstream with the current local branch instead of allowing the creation of a new local branch. Any ideas?
– mMontu
Sep 6 '13 at 12:14
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Check if class already assigned before adding
...ed to an element before adding that class? Will it even have any effect at all?
4 Answers
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Find maximum value of a column and return the corresponding row values using Pandas
...ght hand side of the expression( .max()) returns the index, which in turn calls the complete row of that dataFrame
– penta
Feb 22 '19 at 5:28
add a comment
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How to check permissions of a specific directory?
...ference symbolic links
You might be interested in manpages. That's where all people in here get their nice answers from.
refer to online man pages
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What's the difference between jQuery's replaceWith() and html()?
...() simply replaces the contents.
Note that the replaceWith() will not actually delete the element but simply remove it from the DOM and return it to you in the collection.
An example for Peter: http://jsbin.com/ofirip/2
sh...
How to change the port of Tomcat from 8080 to 80?
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1) Go to conf folder in tomcat installation directory
e.g. C:\Tomcat 6.0\conf\
2) Edit following tag in server.xml file
<Connector connectionTimeout="20000" port="8080" protocol="HTTP/1.1" redirectPort="8443"/>
3) Change the port=8080 value to por...
In what cases do I use malloc and/or new?
I see in C++ there are multiple ways to allocate and free data and I understand that when you call malloc you should call free and when you use the new operator you should pair with delete and it is a mistake to mix the two (e.g. Calling free() on something that was created with the new ...
A simple scenario using wait() and notify() in java
...imple scenario i.e. tutorial that suggest how this should be used, specifically with a Queue?
6 Answers
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Capturing TAB key in text box [closed]
...ng to the next item in the tab order, from occurring.
In Firefox you can call the preventDefault() method on the event object passed to your event handler. In IE, you have to return false from the event handle. The JQuery library provides a preventDefault method on its event object that works in IE...