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How to remove last n characters from every element in the R vector
... an example of what I would do. I hope it's what you're looking for.
char_array = c("foo_bar","bar_foo","apple","beer")
a = data.frame("data"=char_array,"data2"=1:4)
a$data = substr(a$data,1,nchar(a$data)-3)
a should now contain:
data data2
1 foo_ 1
2 bar_ 2
3 ap 3
4 b 4
...
How to commit my current changes to a different branch in Git [duplicate]
...nges should be committed in a branch different to the current one. This usually happens when I want to try out new things or do some testing and I forget to create a new branch beforehand, but I don't want to commit dirty code to the master branch.
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What is the size of ActionBar in pixels?
...king in android version 2.3, but "R.attr.actionBarSize" is working android all version. just use "R.attr.actionBarSize" instead of "android.R.attr.actionBarSize" and etc.
– Nathaniel Jobs
May 20 '16 at 3:23
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Setting variable to NULL after free
... int *nPtr=NULL;. Now, I would agree that this would be redundant, with a malloc following right in the next line. However, if there is code between the declaration and the first initialization, somebody might start using the variable even though it has no value yet. If you null-initialize, you get ...
What's the point of 'const' in the Haskell Prelude?
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It's useful for passing to higher-order functions when you don't need all their flexibility. For example, the monadic sequence operator >> can be defined in terms of the monadic bind operator as
x >> y = x >>= const y
It's somewhat neater than using a lambda
x >> y =...
What reference do I need to use Microsoft.Office.Interop.Excel in .NET?
...ws > assembly > GAC > Microsoft.Office.Interop.Excel > 12.0.0.0_etc > Microsoft.Office.Interop.Excel.dll
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Reset auto increment counter in postgres
...ated the table product with an id column, then the sequence is not simply called product, but rather product_id_seq (that is, ${table}_${column}_seq).
This is the ALTER SEQUENCE command you need:
ALTER SEQUENCE product_id_seq RESTART WITH 1453
You can see the sequences in your database using the...
append to url and refresh page
... a URL in different browsers?
This is my suggested approach:
function URL_add_parameter(url, param, value){
var hash = {};
var parser = document.createElement('a');
parser.href = url;
var parameters = parser.search.split(/\?|&/);
for(var i=0; i < paramete...
What is the convention for word separator in Java package names?
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Packages
The prefix of a unique package name is always written in all-lowercase ASCII letters and should be one of the top-level domain names, currently com, edu, gov, mil, net, org, or one of the English two-letter codes identifying countries as specified in ISO Standard 3166, 1981.
S...
Remove local git tags that are no longer on the remote repository
...cript to compare the tags generated by this list with the tags you have locally. Take a look at git show-ref --tags, which generates the tag names in the same form as git ls-remote).
As an aside, git show-ref has an option that does the opposite of what you'd like. The following command would l...