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What's the fastest way to merge/join data.frames in R?
..., in fact, they are placed on tables which were overwritten before the sql select ever runs and that, in part, accounts for why its so slow. The idea of sqldf is that the data frames in your R session constitute the data base, not the tables in sqlite. Thus each time the code refers to an unqualif...
How to check the version of GitLab?
... later
Log in to GitLab
Click on the drop down menu in the upper right. Select Help.
The GitLab version appears at the top of the page
In earlier versions, like GitLab 9
Log in to GitLab
Click on the drop down menu in the upper left. Select Help.
And then the version appears at the top of th...
How are virtual functions and vtable implemented?
...he difference should be neglible. For a class which just contains a single char member, or no members at all, the difference might be notable.
Apart from that, it is important to note that not every call to a virtual function is a virtual function call. If you have an object of a known type, the co...
Binding an enum to a WinForms combo box, and then setting it
...s.DataSource = Enum.GetValues(typeof(Status));
Getting the enum from the selected item
Status status;
Enum.TryParse<Status>(cbStatus.SelectedValue.ToString(), out status);
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VIM Replace word with contents of paste buffer?
...ister you want (probably ") to put in the contents of that register.
"* - selection register (middle-button paste)
"+ - clipboard register (probably also accessible with ctrl-shift-v via the terminal)
"" - vim's default (unnamed) yank/put/change/delete/substitute register.
Short answer: "_cw^R"
Ed...
Why does “_” (underscore) match “-” (hyphen)?
...u want to use the underscore in like as a literal, you have to escape it:
select * from a where name like '%taz\_manual%.pdf%';
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How to correctly display .csv files within Excel 2013?
... to DATA tab.
Click button From Text in the General External Data section.
Select your CSV file.
Follow the Text Import Wizard. (in step 2, select the delimiter of your text)
http://blogmines.com/blog/how-to-import-text-file-in-excel-2013/
...
How do I remove a folder from source control with TortoiseSVN?
...ose the folder where you
want the working copy exported to. If
you now select the very same path
that your working copy is on as the
target (i.e., you're exporting the
working copy onto itself), TortoiseSVN
will remove all .svn folders of that
working copy.
...
Interface Builder: What are the UIView's Layout iOS 6/7 Deltas for?
...ew to see how this will render in iOS 7 and iOS 6 device.
Quick steps:
Select each immediate children of root view individually and add 20px to its 'Y' value.
Then, select all immediate children collectively and give delta Y as -20px. You can also do this in batch or individually.
...
Azure SQL Database Bacpac Local Restore
...gement Studio 2012
Right click on the Connection > Databases node and select "Import Data-tier application..."
Select "Next" on the introduction step.
Browse, or connect to a storage account where backups are kept.
sh...