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Creating functions in a loop

...cated way which involved using a closure as a "function factory": def make_f(i): def f(): return i return f and in your loop use f = make_f(i) instead of the def statement. share | ...
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Python: Tuples/dictionaries as keys, select, sort

...u wish. For this case, I'd use the following class: class Fruit: def __init__(self, name, color, quantity): self.name = name self.color = color self.quantity = quantity def __str__(self): return "Name: %s, Color: %s, Quantity: %s" % \ (self.name, self...
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Reverse a string in Python

... for readability and reusability, put the slice in a function def reversed_string(a_string): return a_string[::-1] and then: >>> reversed_string('a_string') 'gnirts_a' Longer explanation If you're interested in the academic exposition, please keep reading. There is no built-i...
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Best way to serialize an NSData into a hexadeximal string

...rsion.h #import <Foundation/Foundation.h> @interface NSData (NSData_Conversion) #pragma mark - String Conversion - (NSString *)hexadecimalString; @end NSData+Conversion.m #import "NSData+Conversion.h" @implementation NSData (NSData_Conversion) #pragma mark - String Conversion - (NSStr...
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How to convert boost path type to string?

... canonical is deprecated in newer versions of Boost boost.org/doc/libs/1_48_0/libs/filesystem/v3/doc/… – Brian Jack Nov 30 '14 at 2:59 ...
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Locking a file in Python

...file locking (Linux, Ubuntu, MacOS, etc.) import fcntl, os def lock_file(f): fcntl.lockf(f, fcntl.LOCK_EX) def unlock_file(f): fcntl.lockf(f, fcntl.LOCK_UN) except ModuleNotFoundError: # Windows file locking import msvcrt, os def file_size(f): return o...
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Best way to test if a row exists in a MySQL table

...ng': SELECT * FROM test WHERE texte LIKE '%something%' LIMIT 1 with mysql_num_rows() : 0.039061069488525s. (FASTER) SELECT count(*) as count FROM test WHERE text LIKE '%something% : 16.028197050095s. SELECT EXISTS(SELECT 1 FROM test WHERE text LIKE '%something%') : 0.87045907974243s. SELECT EXIS...
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How to log source file name and line number in Python

...='%Y-%m-%d:%H:%M:%S', level=logging.DEBUG) logger = logging.getLogger(__name__) logger.debug("This is a debug log") logger.info("This is an info log") logger.critical("This is critical") logger.error("An error occurred") Generates this output: 2017-06-06:17:07:02,158 DEBUG [log.py:11] Thi...
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Returning binary file from controller in ASP.NET Web API

....Http; class FileResult : IHttpActionResult { private readonly string _filePath; private readonly string _contentType; public FileResult(string filePath, string contentType = null) { if (filePath == null) throw new ArgumentNullException("filePath"); _filePath = fil...
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Where can I learn how to write C code to speed up slow R functions? [closed]

...: SEXP foobar(){ SEXP ab; PROTECT(ab = allocVector(STRSXP, 2)); SET_STRING_ELT( ab, 0, mkChar("foo") ); SET_STRING_ELT( ab, 1, mkChar("bar") ); UNPROTECT(1); } Using Rcpp, you can write the same function as: SEXP foobar(){ return Rcpp::CharacterVector::create( "foo", "bar" ) ; } ...