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data.table vs dplyr: can one do something well the other can't or does poorly?
... remember is for it to return a list so that each element of the list gets converted to a column.
In dplyr, cannot do that. Have to resort to do() depending on how sure you are as to whether your function would always return a single value. And it is quite slow.
Once again, data.table's synta...
glVertexAttribPointer clarification
Just want to make sure I understand this correctly (I'd ask on SO Chat, but it's dead in there!):
2 Answers
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What are the use cases for selecting CHAR over VARCHAR in SQL?
...R(10) = 10 bytes (4 bytes of waste)
The bottom line is CHAR can be faster and more space-efficient for data of relatively the same length (within two characters length difference).
Note: Microsoft SQL has 2 bytes of overhead for a VARCHAR. This may vary from DB to DB, but generally, there is at lea...
What is the meaning of the term arena in relation to memory?
... arena , but never defines it. I've searched for the meaning of the word and how it relates to memory, and found nothing. Here are a few contexts in which the author uses the term:
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Reading output of a command into an array in Bash
I need to read the output of a command in my script into an array. The command is, for example:
3 Answers
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stringstream, string, and char* conversion confusion
...does the string returned from stringstream.str().c_str() live in memory, and why can't it be assigned to a const char* ?
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Maximum number of characters using keystrokes A, Ctrl+A, Ctrl+C and Ctrl+V
.... Then we iterate through for i up to n, doing two things: pressing A once and pressing select all + copy followed by paste j times (actually j-i-1 below; note the trick here: the contents are still in the clipboard, so we can paste it multiple times without copying each time). We only have to consi...
How to determine if a number is a prime with regex?
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You said you understand this part, but just to emphasize, the String generated has a length equal to the number supplied. So the string has three characters if and only if n == 3.
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The first part of the regex says, "any character, zero or o...
How does database indexing work? [closed]
...a section for data, a pointer to the location of the next node (or block), and both need not be stored contiguously.
Due to the fact that a number of records can only be sorted on one field, we can state that searching on a field that isn’t sorted requires a Linear Search which requires N/2 block...
List of ANSI color escape sequences
...s a series of semicolon-separated parameters.
To say, make text red, bold, and underlined (we'll discuss many other options below) in C you might write:
printf("\033[31;1;4mHello\033[0m");
In C++ you'd use
std::cout<<"\033[31;1;4mHello\033[0m";
In Python3 you'd use
print("\033[31;1;4mHello\0...