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What's the difference between lapply and do.call?
I'm learning R recently and confused by two function: lapply and do.call . It seems that they're just similar to map function in Lisp. But why are there two functions with such a different name? Why doesn't R just use a function called map ?
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How do search engines deal with AngularJS applications?
I see two issues with AngularJS application regarding search engines and SEO:
15 Answers
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How to use Regular Expressions (Regex) in Microsoft Excel both in-cell and loops
How can I use regular expressions in Excel and take advantage of Excel's powerful grid-like setup for data manipulation?
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What is ActiveMQ used for - can we apply messaging concept using a Database?
I looked it up and it used to send messages between 2 systems.
But why? Why wouldn't you just use a Database ?
There must be some feature that ActiveMQ has that Databases do not?
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Which are more performant, CTE or temporary tables?
Which are more performant, CTE or Temporary Tables ?
12 Answers
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Why does pycharm propose to change method to static
The new pycharm release (3.1.3 community edition) proposes to convert the methods that don't work with the current object's state to static.
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How can I hash a password in Java?
I need to hash passwords for storage in a database. How can I do this in Java?
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What is the meaning of “this” in Java?
Normally, I use this in constructors only.
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How to read a text file into a list or an array with Python
I am trying to read the lines of a text file into a list or array in python. I just need to be able to individually access any item in the list or array after it is created.
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Nullable Foreign Key bad practice?
Let's say you have a table Orders with a foreign key to a Customer Id. Now, suppose you want to add an Order without a Customer Id, (whether that should be possible is another question) you would have to make the foreign key NULL... Is that bad practice or would you rather work with a link table bet...