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Determine the number of NA values in a column
I want to count the number of NA values in a data frame column. Say my data frame is called df , and the name of the column I am considering is col . The way I have come up with is following:
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How to convert date to timestamp?
I want to convert date to timestamp, my input is 26-02-2012 . I used
13 Answers
13
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git clone from another directory
I am trying to clone repo from another directory.
8 Answers
8
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Regular Expression: Any character that is NOT a letter or number
I'm trying to figure out the regular expression that will match any character that is not a letter or a number. So characters such as (,,@,£,() etc ...
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PHP parse/syntax errors; and how to solve them
Everyone runs into syntax errors. Even experienced programmers make typos. For newcomers, it's just part of the learning process. However, it's often easy to interpret error messages such as:
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How to alter SQL in “Edit Top 200 Rows” in SSMS 2008
In SQL Server 2008 Management Studio, when I right click on a database table and choose " Select Top 100 Rows ", I can then e.g. easily add a "ORDER BY " statement to the SQL. That works fine .
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Git: See my last commit
I just want to see the files that were committed in the last commit exactly as I saw the list when I did git commit . Unfortunately searching for
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get UTC time in PHP
How can I get UTC/GMT +/- time stamp using PHP's date() function? For example, if I try
12 Answers
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newline in [duplicate]
I'd like to know if it's possible to force a newline to show in the tooltip when using title property of a TD.
something like
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Using JQuery to check if no radio button in a group has been checked
I'm sitting with a problem, I need to check with JQuery if no radio button within a radio button group has been checked, so that I can give the users an javascript error if they forgot to check a option.
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