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Convert a row of a data frame to vector
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Might have been changed in the meantime, but today unlist allows dropping names: identical(unlist(df[1,], use.names = FALSE), as.numeric(df[1,])) (and btw df still is not a sensible name for a data.frame... ;-))
– Andri Signorell
Sep 25 '1...
Programmatically retrieve memory usage on iPhone
...trieve the amount of memory my iPhone app is using at anytime, programmatically. Yes I'm aware about ObjectAlloc/Leaks. I'm not interested in those, only to know if it's possible to write some code and get the amount of bytes being used and report it via NSLog.
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How do you express binary literals in Python?
... memory.
Note that leading zeros in a non-zero decimal number are not allowed.
This is for disambiguation with C-style octal literals, which Python
used before version 3.0.
Some examples of integer literals:
7 2147483647 0o177 0b100110111
3 7922816251...
How do I remove a property from a JavaScript object?
...t object, then that object will, of course, not be garbage collected until all references to it have disappeared.
delete will only work on properties whose descriptor marks them as configurable.
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Why should text files end with a newline?
I assume everyone here is familiar with the adage that all text files should end with a newline. I've known of this "rule" for years but I've always wondered — why?
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URL Encoding using C#
...file name) may be constructed using Uri.EscapeDataString(fileOrFolderName) allowing all non Uri compatible character (spaces, unicode ...). For example to allow any character in filename, use: req =(FtpWebRequest)WebRequest.Create(new Uri(path + "/" + Uri.EscapeDataString(filename))); Using...
How to convert ActiveRecord results into an array of hashes
...d objects to Ruby Hashes despite its name
tasks_records = TaskStoreStatus.all
tasks_records = tasks_records.as_json
# You can now add new records and return the result as json by calling `to_json`
tasks_records << TaskStoreStatus.last.as_json
tasks_records << { :task_id => 10, :sto...
Database, Table and Column Naming Conventions? [closed]
... for Primary Key Columns, Hungarian-esque Constraint Prefixes and worst of all SPACES " " for multi-word table names. Additionally system tables for SQLServer use plurals so it seems AdventureWorks was the black sheep in this bunch.
– Marcus Pope
Mar 20 '12 at...
How to do Base64 encoding in node.js?
...uld be .toString("binary") (atob stands for ascii(base64) to binary, after all)
– 12Me21
Jan 14 at 19:55
@12Me21 I tho...
What is the difference between char array and char pointer in C?
...char* and char[] are different types, but it's not immediately apparent in all cases. This is because arrays decay into pointers, meaning that if an expression of type char[] is provided where one of type char* is expected, the compiler automatically converts the array into a pointer to its first el...