Tutorial by Examples: t

As all threads are running in the same process, all threads have access to the same data. However, concurrent access to shared data should be protected with a lock to avoid synchronization issues. import threading obj = {} obj_lock = threading.Lock() def objify(key, val): print("O...

Code running in different processes do not, by default, share the same data. However, the multiprocessing module contains primitives to help share values across multiple processes. import multiprocessing plain_num = 0 shared_num = multiprocessing.Value('d', 0) lock = multiprocessing.Lock() ...

You can get the current location and local places of user by using the Google Places API. Ar first, you should call the PlaceDetectionApi.getCurrentPlace() method in order to retrieve local business or other places. This method returns a PlaceLikelihoodBuffer object which contains a list of PlaceLi...

To rename remote, use command git remote rename The git remote rename command takes two arguments: An existing remote name, for example : origin A new name for the remote, for example : destination Get existing remote name git remote # origin Check existing remote with URL git remote -...

Informally, a monad is a container of elements, notated as F[_], packed with 2 functions: flatMap (to transform this container) and unit (to create this container). Common library examples include List[T], Set[T] and Option[T]. Formal definition Monad M is a parametric type M[T] with two operatio...

Returns a sub string starting with the left most char of a string and up to the maximum length specified. Parameters: character expression. The character expression can be of any data type that can be implicitly converted to varchar or nvarchar, except for text or ntext max length. An integer n...

Returns a sub string that is the right most part of the string, with the specified max length. Parameters: character expression. The character expression can be of any data type that can be implicitly converted to varchar or nvarchar, except for text or ntext max length. An integer number betwe...

Returns a substring that starts with the char that's in the specified start index and the specified max length. Parameters: Character expression. The character expression can be of any data type that can be implicitly converted to varchar or nvarchar, except for text or ntext. Start index. A nu...

SQL Server 2012 Returns a string that is the result of two or more strings joined together. CONCAT accepts two or more arguments. SELECT CONCAT('This', ' is', ' my', ' string') -- returns 'This is my string' Note: Unlike concatenating strings using the string concatenation operator (+), when ...

Returns a character expression (varchar or nvarchar) after removing all leading white spaces, i.e., white spaces from the left through to the first non-white space character. Parameters: character expression. Any expression of character or binary data that can be implicitly converted to varcher,...

Returns a character expression (varchar or nvarchar) after removing all trailing white spaces, i.e., spaces from the right end of the string up until the first non-white space character to the left. Parameters: character expression. Any expression of character or binary data that can be implicit...

The switch statement is a control statement that selects a switch section to execute from a list of candidates. A switch statement includes one or more switch sections. Each switch section contains one or more case labels followed by one or more statements. If no case label contains a matching value...

An interface contains the signatures of methods, properties and events. The derived classes defines the members as the interface contains only the declaration of the members. An interface is declared using the interface keyword. interface IProduct { decimal Price { get; } } class Product...

List comprehensions are a syntactic construct to create a list based on existing lists. In erlang a list comprehension has the form [Expr || Qualifier1, ..., QualifierN]. Where qualifiers are either generators Pattern <- ListExpr or filter like integer(X) evaluating to either true or false. Th...

plot() can take arguments that get passed on to matplotlib to style the plot in different ways. df.plot(style='o') # plot as dots, not lines df.plot(style='g--') # plot as green dashed line df.plot(style='o', markeredgecolor='white') # plot as dots with white edge

By default, plot() creates a new figure each time it is called. It is possible to plot on an existing axis by passing the ax parameter. plt.figure() # create a new figure ax = plt.subplot(121) # create the left-side subplot df1.plot(ax=ax) # plot df1 on that subplot ax = plt.subplot(122) # c...

All integers or pointers can be used in an expression that is interpreted as "truth value". int main(int argc, char* argv[]) { if (argc % 4) { puts("arguments number is not divisible by 4"); } else { puts("argument number is divisible by 4"); } ... ...

ScopedTypeVariables let you refer to universally quantified types inside of a declaration. To be more explicit: import Data.Monoid foo :: forall a b c. (Monoid b, Monoid c) => (a, b, c) -> (b, c) -> (a, b, c) foo (a, b, c) (b', c') = (a :: a, b'', c'') where (b'', c'') = (b <&g...

If an array happens to have one or more nil elements and these need to be removed, the Array#compact or Array#compact! methods can be used, as below. array = [ 1, nil, 'hello', nil, '5', 33] array.compact # => [ 1, 'hello', '5', 33] #notice that the method returns a new copy of the array w...

In this example, a model will learn to classify fruits given certain features, using the Labels for training. WeightColorLabel0.5greenapple0.6purpleplum3greenwatermelon0.1redcherry0.5redapple Here the a model will take Weight and Color as features to predict the Label. For instance [0.15, 'red'] s...