Tutorial by Examples: co

Longest Common Subsequence Explanation

One of the most important implementations of Dynamic Programming is finding out the Longest Common Subsequence. Let's define some of the basic terminologies first. Subsequence: A subsequence is a sequence that can be derived from another sequence by deleting some elements without changing the orde...

algorithm • Longest Common Subsequence

Comprehensions

You can do neat things via the results of Array "comprehensions"... Like assign multiple variables... from the result of a looping for statement... [express,_] = (require x for x in ['express','underscore']) Or a syntactically sweet version of a "mapped" function call, etc.....

coffeescript • Arrays

Get the top most UIViewController

A common approach to get the top most UIViewController is to get the RootViewController of your active UIWindow. I wrote an extension for this: extension UIApplication { func topViewController(_ base: UIViewController? = UIApplication.shared.keyWindow?.rootViewController) -> UIViewController ...

iOS • App wide operations

Enable the internal logger in nlog.config

In case of problems, enable the internal logger <nlog internalLogFile="c:\log.txt" internalLogLevel="Trace"> <targets>  </targets> <rules>  </rules&gt...

nlog • Troubleshooting NLog

Two-way conversions

Descriptor objects can allow related object attributes to react to changes automatically. Suppose we want to model an oscillator with a given frequency (in Hertz) and period (in seconds). When we update the frequency we want the period to update, and when we update the period we want the frequency ...

Python Language • Descriptor

Before Submit: Validate record before it is committed to database

For this example, we want to make sure that any Employee who is marked as a Project Resource also has an appropriate Labor Cost defined. // 1.0, Revealing Module pattern var myNamespace = myNamespace || {}; myNamespace.example = (function () { /** * User Event 1.0 example detailing...

netsuite • User Event: Before and After Submit events

Restrict execution based on the context that triggered the User Event

In SuiteScript 1.0, we retrieve the current execution context using nlapiGetContext().getExecutionContext(), then we compare the result to the appropriate raw Strings. // 1.0 in Revealing Module pattern var myNamespace = myNamespace || {}; myNamespace.example = (function () { var exports =...

netsuite • User Event: Before Load event

Collect google spreadsheet data into pandas dataframe

Sometimes we need to collect data from google spreadsheets. We can use gspread and oauth2client libraries to collect data from google spreadsheets. Here is a example to collect data: Code: from __future__ import print_function import gspread from oauth2client.client import SignedJwtAssertionCred...

pandas • Reading files into pandas DataFrame

Product Collection

$productCollection = Mage::getModel('catalog/product')->getCollection(); Selecting the specific Attribute $productCollection->addAttributeToSelect(array('name', 'product_url', 'small_image')); Selecting the All Attributes $productCollection->addAttributeToSelect('*'); Add Filter ...

magento • Collections

Violation of CLS rule: Inherit from non CLSComplaint class

using System; [assembly:CLSCompliant(true)] namespace CLSDoc { [CLSCompliant(false)] public class Animal { public int age = 0; } //Warning CS3009 'Dog': base type 'Animal' is not CLS-compliant public class Dog : Animal { } }

C# Language • CLSCompliantAttribute

Const Correct Class Design

In a const-correct class, all member functions which don't change logical state have this cv-qualified as const, indicating that they don't modify the object (apart from any mutable fields, which can freely be modified even in const instances); if a const cv-qualified function returns a reference, t...

C++ • Const Correctness

Const Correct Function Parameters

In a const-correct function, all passed-by-reference parameters are marked as const unless the function directly or indirectly modifies them, preventing the programmer from inadvertently changing something they didn't mean to change. This allows the function to take both const and non-cv-qualified ...

C++ • Const Correctness

Compute nth Fibonacci number

;;Find the nth Fibonacci number for any n > 0. ;; Precondition: n > 0, n is an integer. Behavior undefined otherwise. (defun fibonacci (n) (cond ( ;; Base case. ;; The first two Fibonacci numbers (indices 1 and 2) are 1 by defin...

common-lisp • Recursion

Objective C code to make selected corner of a UiView rounded

First import #import <QuartzCore/QuartzCore.h> into your ViewController class. Here is how I set my view in code UIView *view1=[[UIView alloc]init]; view1.backgroundColor=[UIColor colorWithRed:255/255.0 green:193/255.0 blue:72/255.0 alpha:1.0]; CGRect view1Frame = view1.frame; view1Frame....

iOS • Make selective UIView corners rounded

Objective C code to convert HTML string to NSAttributedString and Vice Versa

HTML to NSAttributedString conversion Code :- //HTML String NSString *htmlString=[[NSString alloc]initWithFormat:@"<!DOCTYPE html><html><body><h1>My First Heading</h1><p>My first paragraph.</p></body></html>"]; //Converting HTML s...

iOS • Convert HTML to NSAttributed string and vice verse

Class, Interface, Record usage

// Record type Ribbon = {Length:int} // Class type Line(len:int) = member x.Length = len type IHaveALength = abstract Length:int let inline getLength s = (^a: (member Length: _) s) let ribbon = {Length=1} let line = Line(3) let someLengthImplementer = { new IHaveALength wit...

F# • Statically Resolved Type Parameters

Const Correctness as Documentation

One of the more useful things about const correctness is that it serves as a way of documenting code, providing certain guarantees to the programmer and other users. These guarantees are enforced by the compiler due to constness, with a lack of constness in turn indicating that code doesn't provide...

C++ • Const Correctness

Setting place type filters for PlaceAutocomplete

In some scenarios, we might want to narrow down the results being shown by PlaceAutocomplete to a specific country or maybe to show only Regions. This can be achieved by setting an AutocompleteFilter on the intent. For example, if I want to look only for places of type REGION and only belonging to I...

Android • Android Places API

Installing from Configuration

Castle enables to register components also via XML Registration. //To install from the app/web.config container.Install(Configuration.FromAppConfig()); //To install from an xml file Configuration.FromXmlFile("relative_path_to_file.xml"); Read Castle's documentation for "What ...

castle-windsor • Installers

A real-world example from a Household controller

Background: The Household entity includes a set of options, each of which is an entity that is managed in an admin backend. Each option has a boolean enabled flag. If a previously enabled option is set to disabled it will need to be persisted in later Household edits, but cannot be edited away. T...

symfony2 • Sending options to a form class