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Passing command line arguments to R CMD BATCH
.... I am now at the point where I would like to pass an argument to the command, but am having some issues getting it working. If I do R CMD BATCH my_script.R blabla then blabla becomes the output file, rather than being interpreted as an argument available to the R script being executed.
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pandas: How do I split text in a column into multiple rows?
I'm working with a large csv file and the next to last column has a string of text that I want to split by a specific delimiter. I was wondering if there is a simple way to do this using pandas or python?
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Datatype for storing ip address in SQL Server
...s (no, not even an INT32/INT(4), the numeric textual form that we all know and love (255.255.255.255) being just the display conversion of its binary content).
If you do it this way, you will want functions to convert to and from the textual-display format:
Here's how to convert the textual displa...
How can I access and process nested objects, arrays or JSON?
I have a nested data structure containing objects and arrays. How can I extract the information, i.e. access a specific or multiple values (or keys)?
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Why are these constructs using pre and post-increment undefined behavior?
... can't predict the behavior when the code is run.
As far as I know, the standard doesn't explicitly say why the concept of undefined behavior exists. In my mind, it's simply because the language designers wanted there to be some leeway in the semantics, instead of i.e. requiring that all implementa...
How do iOS Push Notifications work?
...ered to receive those notifications. Each device establishes an accredited and encrypted IP connection with the service and receives notifications over this persistent connection. Providers connect with APNs through a persistent and secure channel while monitoring incoming data intended for their cl...
Why is [1,2] + [3,4] = “1,23,4” in JavaScript?
...d for arrays.
What happens is that Javascript converts arrays into strings and concatenates those.
Update
Since this question and consequently my answer is getting a lot of attention I felt it would be useful and relevant to have an overview about how the + operator behaves in general also.
So, h...
Quick-and-dirty way to ensure only one instance of a shell script is running at a time
What's a quick-and-dirty way to make sure that only one instance of a shell script is running at a given time?
40 Answers
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How can I exclude all “permission denied” messages from “find”?
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Note:
* This answer probably goes deeper than the use case warrants, and find 2>/dev/null may be good enough in many situations. It may still be of interest for a cross-platform perspective and for its discussion of some advanced shell techniques in the interest of finding a solution that i...
Get the week start date and week end date from week number
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You can find the day of week and do a date add on days to get the start and end dates..
DATEADD(dd, -(DATEPART(dw, WeddingDate)-1), WeddingDate) [WeekStart]
DATEADD(dd, 7-(DATEPART(dw, WeddingDate)), WeddingDate) [WeekEnd]
You probably also want to l...