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Evaluate expression given as a string
...ied. For example, if you have a pre-defined variable name equal to "David" and you reassign using eval(parse(text = "name") == "Alexander", you will get an error because eval & parse do not return an R expression that can be evaluated.
– Crt
Aug 1 '16 at 22...
What happens to an open file handle on Linux if the pointed file gets moved or deleted
What happens to an open file handle on Linux if the pointed file meanwhile gets:
7 Answers
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Efficiency of Java “Double Brace Initialization”?
...e all classes which were generated when I was making a simple application, and used copious amounts of anonymous inner classes -- each class will be compiled into a separate class file.
The "double brace initialization", as already mentioned, is an anonymous inner class with an instance initializat...
How to parse freeform street/postal address out of text, and into components
We do business largely in the United States and are trying to improve user experience by combining all the address fields into a single text area. But there are a few problems:
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Programmatically creating Markdown tables in R with KnitR
I am just starting to learn about KnitR and the use of Markdown in generating R documents and reports. This looks to be perfect for a lot of the day to day reporting that I have to do with my job. However, one thing that I'm not seeing is an easy way to print data frames and tables using Markdown fo...
Twitter API returns error 215, Bad Authentication Data
... to obtain following keys you need to sign up with https://dev.twitter.com and create application.
<?php
$token = 'YOUR_TOKEN';
$token_secret = 'YOUR_TOKEN_SECRET';
$consumer_key = 'CONSUMER_KEY';
$consumer_secret = 'CONSUMER_SECRET';
$host = 'api.twitter.com';
$method = 'GET';
$path = '/1.1/st...
Get top 1 row of each group
...nt to:
maintain status in 2 places
preserve status history
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As it stands, you preserve status history. If you want latest status in the parent table too (which is denormalisation) you'd need a trigger to maintain "status" in the parent. or drop this status history table.
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What is the difference between a cer, pvk, and pfx file?
What is the difference between a cer, pvk, and pfx file? Also, which files do I keep and which am I expected to give to my counter-parties?
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Why not use java.util.logging?
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Disclaimer: I am the founder of log4j, SLF4J and logback projects.
There are objective reasons for preferring SLF4J. For one, SLF4J allows the end-user the liberty to choose the underlying logging framework. In addition, savvier users tend to prefer logback which offe...
How to delete large data of table in SQL without log?
...ty the table, you cannot use WHERE clause to limit the rows being deleted and no triggers will be fired.
On the other hand if you are deleting more than 80-90 Percent of the data, say if you have total of 11 Million rows and you want to delete 10 million another way would be to Insert these 1 mill...