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Subset of rows containing NA (missing) values in a chosen column of a data frame
We have a data frame from a CSV file. The data frame DF has columns that contain observed values and a column ( VaR2 ) that contains the date at which a measurement has been taken. If the date was not recorded, the CSV file contains the value NA , for missing data.
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git: diff between file in local repo and origin
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If [remote-path] and [local-path] are the same, you can do
$ git fetch origin master
$ git diff origin/master -- [local-path]
Note 1: The second command above will compare against the locally stored remote tracking branch. The fetch command is required to update the remot...
AWS Error Message: A conflicting conditional operation is currently in progress against this resourc
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I got the same error message, when I did following:
created a bucket - it went by default to US region (used AWSCLI)
realized, the bucket shall go to EU region and deleted it (used AWS console)
(few minutes later) tried to create the bucket, specifying the EU region
At step 3, AWS cons...
Differences and relationship between glActiveTexture and glBindTexture
From what I gather, glActiveTexture sets the active "texture unit". Each texture unit can have multiple texture targets (usually GL_TEXTURE_1D, 2D, 3D or CUBE_MAP).
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How to return 2 values from a Java method?
I am trying to return 2 values from a Java method but I get these errors. Here is my code:
14 Answers
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Deleting queues in RabbitMQ
I have a few queues running with RabbitMQ. A few of them are of no use now, how can I delete them? Unfortunately I had not set the auto_delete option.
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Most concise way to convert a Set to a List
For example, I am currently doing this:
6 Answers
6
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How to get the first line of a file in a bash script?
I have to put in a bash variable the first line of a file. I guess it is with the grep command, but it is any way to restrict the number of lines?
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WPF - How to force a Command to re-evaluate 'CanExecute' via its CommandBindings
I have a Menu where each MenuItem in the hierarchy has its Command property set to a RoutedCommand I've defined. The associated CommandBinding provides a callback for the evaluation of CanExecute which controls the enabled state of each MenuItem .
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How to find all tables that have foreign keys that reference particular table.column and have values
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Here you go:
USE information_schema;
SELECT *
FROM
KEY_COLUMN_USAGE
WHERE
REFERENCED_TABLE_NAME = 'X'
AND REFERENCED_COLUMN_NAME = 'X_id';
If you have multiple databases with similar tables/column names you may also wish to...