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Swift Add this extension to UIImage : extension UIImage { func maskWithColor(color: UIColor) -> UIImage? { let maskImage = self.CGImage let width = self.size.width let height = self.size.height let bounds = CGRectMake(0, 0, width, height) ...

with q command we could simplify a lot of tedious work in vim. example 1. generate array sequence (1 to 20). STEP 1. press i to enter insert mode, input 1 1 STEP 2. Record following action: "append the last number to the next line, and increment the number" type esc to exit input...

The Compat.jl package enables using some new Julia features and syntax with older versions of Julia. Its features are documented on its README, but a summary of useful applications is given below. 0.5.0 Unified String type In Julia v0.4, there were many different types of strings. This system was...

NSArray *aryFName = @[ @"Alice", @"Bob", @"Charlie", @"Quentin" ]; NSArray *aryLName = @[ @"Smith", @"Jones", @"Smith", @"Alberts" ]; NSArray *aryAge = @[ @24, @27, @33, @31 ]; //Create a Custom class with prope...

Without replacement With combn, each vector appears in a column: combn(LETTERS, 3) # Showing only first 10. [,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9] [,10] [1,] "A" "A" "A" "A" "A" "A" "A" "A" &quo...

Without replacement choose(length(LETTERS), 5) [1] 65780 With replacement length(letters)^5 [1] 11881376

Items are added to a Collection by calling its .Add method: Syntax: .Add(item, [key], [before, after]) ParameterDescriptionitemThe item to store in the Collection. This can be essentially any value that a variable can be assigned to, including primitive types, arrays, objects, and Nothing.keyO...

Items are removed from a Collection by calling its .Remove method: Syntax: .Remove(index) ParameterDescriptionindexThe item to remove from the Collection. If the value passed is a numeric type or Variant with a numeric sub-type, it will be interpreted as a numeric index. If the value passed i...

The number of items in a Collection can be obtained by calling its .Count function: Syntax: .Count() Sample Usage: Public Sub Example() Dim foo As New Collection With foo .Add "One" .Add "Two" .Add "Three" .Add...

Items can be retrieved from a Collection by calling the .Item function. Syntax: .Item(index) ParameterDescriptionindexThe item to retrieve from the Collection. If the value passed is a numeric type or Variant with a numeric sub-type, it will be interpreted as a numeric index. If the value pas...

Keys Unlike a Scripting.Dictionary, a Collection does not have a method for determining if a given key exists or a way to retrieve keys that are present in the Collection. The only method to determine if a key is present is to use the error handler: Public Function KeyExistsInCollection(ByVal key...

The easiest way to clear all of the items from a Collection is to simply replace it with a new Collection and let the old one go out of scope: Public Sub Example() Dim foo As New Collection With foo .Add "One" .Add "Two" .Add "Thre...

Using variables in a string You can concatenate strings using variables inside a double-quoted string. This does not work with properties. $string1 = "Power" $string2 = "Shell" "Greetings from $string1$string2" Using the + operator You can also join strings usin...

The -Command parameter is used to specify commands to be executed on launch. It supports multiple data inputs. -Command <string> You can specify commands to executed on launch as a string. Multiple semicolon ;-separated statements may be executed. >PowerShell.exe -Command "(Get-Date...

def get_autocomplete(text): query = """ start n = node(*) where n.name =~ '(?i)%s.*' return n.name,labels(n) limit 10; """ query = query % (text) obj = [] for res in graph.cypher.execute(query): # print res[0],res[1] obj.a...

Nested list comprehensions, unlike list comprehensions with nested loops, are List comprehensions within a list comprehension. The initial expression can be any arbitrary expression, including another list comprehension. #List Comprehension with nested loop [x + y for x in [1, 2, 3] for y in [3, 4...

Supposing you have setup a django project, and the settings file is in an app named main, this is how you initialize your code import os, sys # Setup environ sys.path.append(os.getcwd()) os.environ.setdefault("DJANGO_SETTINGS_MODULE", "main.settings") # Setup django imp...

Magento has a powerful set of methods to filter collections. Since there are two types of Objects that can be contained in collections, we must first determine which type of data we are working with before we can filter it. Magento implements a EAV data model for entities such as products and catego...

Use the double negation syntax to check for truthiness of values. All values correspond to a boolean, irrespective of their type. irb(main):001:0> !!1234 => true irb(main):002:0> !!"Hello, world!" (irb):2: warning: string literal in condition => true irb(main):003:0> !...

You do not need to use double negation in if-else statements. if 'hello' puts 'hey!' else puts 'bye!' end The above code prints 'hey!' on the screen.