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Why can't C compilers rearrange struct members to eliminate alignment padding? [duplicate]
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There are multiple reasons why the C compiler cannot automatically reorder the fields:
The C compiler doesn't know whether the struct represents the memory structure of objects beyond the current compilation unit (for example: a foreign library, a file on disc, network data, CPU page ...
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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PHP Multidimensional Array Searching (Find key by specific value)
...e are other threads about searching multidimensional arrays, but I'm not really understanding enough to apply to my situation. Thanks very much for any help!
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What's the difference between deque and list STL containers?
What is the difference between the two? I mean the methods are all the same. So, for a user, they work identically.
8 Answ...
Delete rows from a pandas DataFrame based on a conditional expression involving len(string) giving K
...df = df.drop(df[<some boolean condition>].index)
Example
To remove all rows where column 'score' is < 50:
df = df.drop(df[df.score < 50].index)
In place version (as pointed out in comments)
df.drop(df[df.score < 50].index, inplace=True)
Multiple conditions
(see Boolean Indexing...
What is the difference between Scala's case class and class?
...xclusively depend on their constructor arguments.
This functional concept allows us to
use a compact initialization syntax (Node(1, Leaf(2), None)))
decompose them using pattern matching
have equality comparisons implicitly defined
In combination with inheritance, case classes are used to mimi...
invalid target release: 1.7
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You need to set JAVA_HOME to your jdk7 home directory, for example on Microsoft Windows:
"C:\Program Files\Java\jdk1.7.0_40"
or on OS X:
/Library/Java/JavaVirtualMachines/jdk1.7.0_40.jdk/Contents/Home
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See changes to a specific file using git
...s, but, as far as I understood, it is directory based. This means it gives all the changes of all files on the current directory.
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How do I find all files containing specific text on Linux?
I'm trying to find a way to scan my entire Linux system for all files containing a specific string of text. Just to clarify, I'm looking for text within the file, not in the file name.
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Export specific rows from a PostgreSQL table as INSERT SQL script
....5.3, and my create statement was the same as yours except create view.... All I get in the output is the usual pg_dump comments and SET statements. Not sure where I'm going wrong.
– poshest
Nov 20 '16 at 15:19
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