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Sometimes, you may want something to occur regardless of whatever exception happened, for example, if you have to clean up some resources. The finally block of a try clause will happen regardless of whether any exceptions were raised. resource = allocate_some_expensive_resource() try: do_stu...

To find some number (more than one) of largest or smallest values of an iterable, you can use the nlargest and nsmallest of the heapq module: import heapq # get 5 largest items from the range heapq.nlargest(5, range(10)) # Output: [9, 8, 7, 6, 5] heapq.nsmallest(5, range(10)) # Output: [...

Packages are collections of R functions, data, and compiled code in a well-defined format. Public (and private) repositories are used to host collections of R packages. The largest collection of R packages is available from CRAN. Using CRAN A package can be installed from CRAN using following code...

We will model the process #Load the forecast package library(forecast) #Generate an AR1 process of length n (from Cowpertwait & Meltcalfe) # Set up variables set.seed(1234) n <- 1000 x <- matrix(0,1000,1) w <- rnorm(n) # loop to create x for (t in 2:n) x[t] <- 0.7...

Variables of character type or of a derived type with length parameter may have the length parameter either assumed or deferred. The character variable name character(len=len) name is of length len throughout execution. Conversely the length specifier may be either character(len=*) ... ! Ass...

if ([object respondsToSelector:@selector(someOptionalMethodInProtocol:)]) { [object someOptionalMethodInProtocol:argument]; }

Move Blue to the beginning of the array: NSMutableArray *myColors = [NSMutableArray arrayWithObjects: @"Red", @"Green", @"Blue", @"Yellow", nil]; NSUInteger fromIndex = 2; NSUInteger toIndex = 0; id blue = [[[self.array objectAtIndex:fromIndex] retain]...

Evaluates to the second argument if and only if both of the arguments are truthy. Otherwise evaluates to the first falsey argument. x = True y = True z = x and y # z = True x = True y = False z = x and y # z = False x = False y = True z = x and y # z = False x = False y = False z =...

Deleting files The unlink function deletes a single file and returns whether the operation was successful. $filename = '/path/to/file.txt'; if (file_exists($filename)) { $success = unlink($filename); if (!$success) { throw new Exception("Cannot delete $filename&qu...

Constants can be defined inside classes using a const keyword. class Foo { const BAR_TYPE = "bar"; // reference from inside the class using self:: public function myMethod() { return self::BAR_TYPE; } } // reference from outside the class using <Class...

You can use the filter(_:) method on SequenceType in order to create a new array containing the elements of the sequence that satisfy a given predicate, which can be provided as a closure. For example, filtering even numbers from an [Int]: let numbers = [22, 41, 23, 30] let evenNumbers = number...

Any data structure that supports __getitem__ can have their nested structure formatted: person = {'first': 'Arthur', 'last': 'Dent'} '{p[first]} {p[last]}'.format(p=person) # 'Arthur Dent' Object attributes can be accessed using getattr(): class Person(object): first = 'Zaphod' la...

The two parameters to Range are the first number and the count of elements to produce (not the last number). // prints 1,2,3,4,5,6,7,8,9,10 Console.WriteLine(string.Join(",", Enumerable.Range(1, 10))); // prints 10,11,12,13,14 Console.WriteLine(string.Join(",", Enumerable.R...

Due to Node's asynchronous nature, creating or using a directory by first: checking for its existence with fs.stat(), then creating or using it depending of the results of the existence check, can lead to a race condition if the folder is created between the time of the check and the time of ...

cursor: value; Examples: ValueDescriptionnoneNo cursor is rendered for the elementautoDefault. The browser sets a cursorhelpThe cursor indicates that help is availablewaitThe cursor indicates that the program is busymoveThe cursor indicates something is to be movedpointerThe cursor is a pointe...

The nodemon package makes it possible to automatically reload your program when you modify any file in the source code. Installing nodemon globally npm install -g nodemon (or npm i -g nodemon) Installing nodemon locally In case you don't want to install it globally npm install --save-dev nodemo...

Exporting a macro to allow other modules to use it: #[macro_export] // ^~~~~~~~~~~~~~~ Think of it as `pub` for macros. macro_rules! my_macro { (..) => {..} } Using macros from other crates or modules: #[macro_use] extern crate lazy_static; // ^~~~~~~~~~~~ Must add this in ord...

Say we have an enum DayOfWeek: enum DayOfWeek { SUNDAY, MONDAY, TUESDAY, WEDNESDAY, THURSDAY, FRIDAY, SATURDAY; } An enum is compiled with a built-in static valueOf() method which can be used to lookup a constant by its name: String dayName = DayOfWeek.SUNDAY.name(); assert dayName.equal...

This topic specifically talks about UTF-8 and considerations for using it with a database. If you want more information about using databases in PHP then checkout this topic. Storing Data in a MySQL Database: Specify the utf8mb4 character set on all tables and text columns in your database. ...

The following code will print the arguments to the program, and the code will attempt to convert each argument into a number (to a long): #include <stdlib.h> #include <stdio.h> #include <errno.h> #include <limits.h> int main(int argc, char* argv[]) { for (int ...