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Pattern matching on tuples uses the tuple constructors. To match a pair for example, we'd use the (,) constructor: myFunction1 (a, b) = ... We use more commas to match tuples with more components: myFunction2 (a, b, c) = ... myFunction3 (a, b, c, d) = ... Tuple patterns can contain comple...

Use the uncurry function (from Prelude or Data.Tuple) to convert a binary function to a function on tuples. uncurry (+) (1, 2) -- computes 3 uncurry map (negate, [1, 2, 3]) -- computes [-1, -2, -3] uncurry uncurry ((+), (1, 2)) -- computes 3 map (uncurry (+)) [(1, 2), (3, 4), (5, 6)] -- co...

Use the curry function (from Prelude or Data.Tuple) to convert a function that takes tuples to a function that takes two arguments. curry fst 1 2 -- computes 1 curry snd 1 2 -- computes 2 curry (uncurry f) -- computes the same as f import Data.Tuple (swap) curry swap 1 2 -- computes (2, 1...

Android Activity package com.example.myapp; import android.os.Bundle; import android.app.Activity; import android.webkit.WebView; public class WebViewActivity extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceSta...

Basic Example package com.example.myapp; import android.os.Bundle; import android.app.Activity; import android.webkit.WebView; public class WebViewActivity extends Activity { private Webview webView; @Override protected void onCreate(Bundle savedInstanceState) { ...

Caffe has a build-in input layer tailored for image classification tasks (i.e., single integer label per input image). This input "Data" layer is built upon an lmdb or leveldb data structure. In order to use "Data" layer one has to construct the data structure with all training d...

RSA can be used to create a message signature. A valid signature can only be generated with access to the private RSA key, validating on the other hand is possible with merely the corresponding public key. So as long as the other side knows your public key they can verify the message to be signed by...

What: Caching can optimize computation in Spark. Caching stores data in memory and is a special case of persistence. Here is explained what happens when you cache an RDD in Spark. Why: Basically, caching saves an interim partial result - usually after transformations - of your original data. So, ...

SQL Server 2012 In Transact SQL , you may define an object as Date (or DateTime) using the [DATEFROMPARTS][1] (or [DATETIMEFROMPARTS][1]) function like following: DECLARE @myDate DATE=DATEFROMPARTS(1988,11,28) DECLARE @someMoment DATETIME=DATEFROMPARTS(1988,11,28,10,30,50,123) The parameter...

From dataframe: mtrdd <- createDataFrame(sqlContext, mtcars) From csv: For csv's, you need to add the csv package to the environment before initiating the Spark context: Sys.setenv('SPARKR_SUBMIT_ARGS'='"--packages" "com.databricks:spark-csv_2.10:1.4.0" "sparkr-shel...

Installation via Composer The easiest way to install the Incubator is by using Composer. Install Composer and create a new composer.json file in the root of your project. |-- app |-- public | `-- index.php |-- vendor |-- composer.json Add the following content to the composer.json file. ...

Dirty reads (or uncommitted reads) are reads of rows which are being modified by an open transaction. This behavior can be replicated by using 2 separate queries: one to open a transaction and write some data to a table without committing, the other to select the data to be written (but not yet com...

set var=10 set /a var=%var%+10 echo %var% The final value of var is 20. The second line is not working within a command block used for example on an IF condition or on a FOR loop as delayed expansion would be needed instead of standard environment variable expansion. Here is another, better w...

Foreign keys enables you to define relationship between two tables. One (parent) table need to have primary key that uniquely identifies rows in the table. Other (child) table can have value of the primary key from the parent in one of the columns. FOREIGN KEY REFERENCES constraint ensures that valu...

Let's assume that we have one row in Company table with companyId 1. We can insert row in employee table that has companyId 1: insert into Employee values (17, 'John', 1) However, we cannot insert employee that has non-existing CompanyId: insert into Employee values (17, 'John', 111111) Msg ...

FOREIGN KEY constraint can be added on existing tables that are still not in relationship. Imagine that we have Company and Employee tables where Employee table CompanyId column but don't have foreign key relationship. ALTER TABLE statement enables you to add foreign key constraint on an existing c...

sys.foreignkeys system view returns information about all foreign key relationships in database: select name, OBJECT_NAME(referenced_object_id) as [parent table], OBJECT_NAME(parent_object_id) as [child table], delete_referential_action_desc, update_referential_action_desc from sys.foreign...

Create a set local set = {} -- empty set Create a set with elements by setting their value to true: local set = {pear=true, plum=true} -- or initialize by adding the value of a variable: local fruit = 'orange' local other_set = {[fruit] = true} -- adds 'orange' Add a member to the ...

Bitwise shifting can be thought as "moving" the bits either left or right, and hence changing the value of the data operated on. Left Shift The left shift operator (value) << (shift amount) will shift the bits to the left by (shift amount) bits; the new bits coming in from the righ...

Encapsulation hides implementation details from client code. The Handling QueryClose example demonstrates encapsulation: the form has a checkbox control, but its client code doesn't work with it directly - the checkbox is an implementation detail, what the client code needs to know is whether the s...