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How do I delete rows in a data frame?
... :
mydata[-seq(2, nrow(mydata), by = 2) , ]
Or if you want to subset by selecting odd numbers:
mydata[which(1:nrow(mydata) %% 2 == 1) , ]
Or if you want to subset by selecting odd numbers, version 2:
mydata[which(1:nrow(mydata) %% 2 != 0) , ]
Or if you want to subset by filtering even numbe...
SSH Private Key Permissions using Git GUI or ssh-keygen are too open
..., not Cygwin):
In the windows explorer, right-click your id_rsa file and select Properties
Select the Security tab and click Edit...
Check the Deny box next to Full Control for all groups EXCEPT Administrators
Retry your Git command
...
Cloning a MySQL database on the same MySql instance
...IN db_a:
CREATE TABLE db_b.tbl LIKE db_a.tbl;
INSERT INTO db_b.tbl SELECT * FROM db_a.tbl;
The reason I'm not using the CREATE TABLE ... SELECT ... syntax is to preserve indices. Of course this only copies tables. Views and procedures are not copied, although it can be done in the same man...
What is the IntelliJ shortcut key to create a javadoc comment?
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Do I have to select something? Even if I select the whole file content or select nothing, nothing happens if I run this action. May I am missing something
– Honsa Stunna
Jun 18 '19 at 11:46
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How can I disable ReSharper in Visual Studio and enable it again?
...nd to Ctrl alt A. That might be because Re# has bound the Ctrl W to Extend selection
– Default
Feb 21 '13 at 9:52
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Microsoft.Jet.OLEDB.4.0' provider is not registered on the local machine
...Engine 2010 and force your .NET application to run in 32-bit mode (e.g. by selecting x86 platform in Configuration Manager). And the proper solution is to replace MS Access with a better alternative.
– Massood Khaari
Sep 25 '13 at 5:26
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Where does mongodb stand in the CAP theorem?
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MongoDB selects Consistency over Availability whenever there is a Partition. What it means is that when there's a partition(P) it chooses Consistency(C) over Availability(A).
To understand this, Let's understand how MongoDB does rep...
How to organize a node app that uses sequelize?
... did not quite understand Sequelize, but to me doing things more than just selecting from one table wasn't really convenient. And where ordinarily you would use select from two or more tables, or a union in pure SQL, you would have to run separate queries, and with the async nature of Node it's just...
Why am I getting 'Assembly '*.dll' must be strong signed in order to be marked as a prerequisite.'?
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When using ClickOnce, this check box is automatically selected each time the application is published with the Publish wizard. See msdn.microsoft.com/en-us/library/1sfbfyk0.aspx for more information.
– David Murdoch
Apr 28 '15 at 16:54
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Entity Framework: There is already an open DataReader associated with this Command
...al commands executed on single connection (or single command with multiple selects) while next DataReader is executed before first one has completed the reading. The only way to avoid the exception is to allow multiple nested DataReaders = turn on MultipleActiveResultSets. Another scenario when this...