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How to get the last value of an ArrayList
...seem very efficient to me. I come from C++, where there are actual front() and back() methods on the list object, that are internally implemented with head and tail references. Is there a similar mechanism in Java?
– Brady
Oct 13 '14 at 9:18
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How can you use an object's property in a double-quoted string?
... # yields "abc.Length"
"$($bar.Length)" # yields "3"
PowerShell only expands variables in those cases, nothing more. To force evaluation of more complex expressions, including indexes, properties or even complete calculations, you have to enclose those in the subexpression operator $( ) which cau...
XPath to find elements that does not have an id or class
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Pretty straightforward:
//tr[not(@id) and not(@class)]
That will give you all tr elements lacking both id and class attributes. If you want all tr elements lacking one of the two, use or instead of and:
//tr[not(@id) or not(@class)]
When attributes and eleme...
How to delete or add column in SQLITE?
...e
SQLite supports a limited subset of ALTER TABLE. The ALTER TABLE command in SQLite allows the user to rename a table or to add a new column to an existing table. It is not possible to rename a column, remove a column, or add or remove constraints from a table.
You can:
create new table as ...
Should I use a data.frame or a matrix?
When should one use a data.frame , and when is it better to use a matrix ?
6 Answers
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jQuery How to Get Element's Margin and Padding?
...ndering - how using jQuery - I can get an elements formatted total padding and margin etc ? i.e. 30px 30px 30px 30px or 30px 5px 15px 30px etc
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How do I update if exists, insert if not (AKA “upsert” or “merge”) in MySQL?
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@blub: If you create a unique key on geb and topic it will work (ALTER TABLE table ADD UNIQUE geb_by_topic (geb, topic)).
– chaos
Aug 2 '09 at 13:43
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How to write a cron that will run a script every day at midnight?
I have heard crontab is a good choice, but how do I write the line and where do I put it on the server?
6 Answers
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git pull from master into the development branch
I have a branch called dmgr2 (development) and I want to pull from the master branch (live site) and incorporate all the changes into my development branch. is there a better way to do this?
here is what I had planned on doing, after committing changes:
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Importing CSV with line breaks in Excel 2007
...king on the file in Explorer.
I have a CSV file that is in UTF-8 encoding and contains newlines in some cells. If I open this file from Excel's File->Open menu, the "import CSV" wizard pops up and the file cannot be correctly imported: the newlines start a new row even when quoted. If I open thi...