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How to test if list element exists?
...es(foo) # TRUE
"b" %in% names(foo) # TRUE
"c" %in% names(foo) # FALSE
...and foo[["a"]] is safer than foo$a, since the latter uses partial matching and thus might also match a longer name:
x <- list(abc=4)
x$a # 4, since it partially matches abc
x[["a"]] # NULL, no match
[UPDATE] So, back t...
How do I make an HTML button not reload the page
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This works well, and particularly in the case of Chrome (for which the accepted answer doesn't)
– hobailey
Mar 3 '16 at 14:15
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How to kill an Android activity when leaving it so that it cannot be accessed from the back button?
In an given Android activity, I would like to start a new activity for the user at some point. Once they leave the first activity and arrive at the second, the first activity is stale and I want to remove it completely so it can not be accessed again from the back button.
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Why doesn't Console.Writeline, Console.Write work in Visual Studio Express?
I just open a console application and I type
19 Answers
19
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Software keyboard resizes background image on Android
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Ok I fixed it by using
android:windowSoftInputMode="stateVisible|adjustPan"
entry inside <Activity > tag in manifest file. I think it was caused by having ScrollView inside the Activity.
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How can I search sub-folders using glob.glob module?
I want to open a series of subfolders in a folder and find some text files and print some lines of the text files. I am using this:
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How to get the current branch name in Git?
I'm from a Subversion background and, when I had a branch, I knew what I was working on with "These working files point to this branch".
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Timeout jQuery effects
...lay/
$('.notice').fadeIn().delay(2000).fadeOut('slow');
Note: $.show() and $.hide() by default are not queued, so if you want to use $.delay() with them, you need to configure them that way:
$('.notice')
.show({duration: 0, queue: true})
.delay(2000)
.hide({duration: 0, queue: true}...
heroku - how to see all the logs
...ve a small app on heroku. Whenever I want to see the logs I go to the command line and do
19 Answers
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What text editor is available in Heroku bash shell? [closed]
...ust install:
heroku plugins:install https://github.com/naaman/heroku-vim
And use:
heroku vim
The heroku vim command will drop you into a bash shell with vim installed on your $PATH. All you have to do is retrain your fingers to type heroku vim instead of heroku run bash.
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