Tutorial by Examples: re

Assume you've initialized a project with the following directory structure: /build app.js Then you add everything so you've created so far and commit: git init git add . git commit -m "Initial commit" Git will only track the file app.js. Assume you added a build step to your applicat...

You can give alias names to a struct: typedef struct Person { char name[32]; int age; } Person; Person person; Compared to the traditional way of declaring structs, programmers wouldn't need to have struct every time they declare an instance of that struct. Note that the name Pers...

[HttpPost] public ActionResult ContactUs(ContactUsModel contactObject) { // This line checks to see if the Model is Valid by verifying each Property in the Model meets the data validation rules if(ModelState.IsValid) { } return View(contactObject); } The model class p...

def addNumbers = { a, b -> a + b } addNumbers(-7, 15) // returns 8

['cat', 'dog', 'fish'].collect { it.length() } it is the default name of the parameter if you have a single parameter and do not explicitly name the parameter. You can optionally declare the parameter as well. ['cat', 'dog', 'fish'].collect { animal -> animal.length() }

Build a text report showing the main classification metrics, including the precision and recall, f1-score (the harmonic mean of precision and recall) and support (the number of observations of that class in the training set). Example from sklearn docs: from sklearn.metrics import classification_re...

If-statements can be expressions: val str = if (condition) "Condition met!" else "Condition not met!" Note that the else-branch is not optional if the if-statement is used as an expression. This can also been done with a multi-line variant with curly brackets and multiple el...

Like if, when can also be used as an expression: val greeting = when (x) { "English" -> "How are you?" "German" -> "Wie geht es dir?" else -> "I don't know that language yet :(" } print(greeting) To be used as an express...

(This pitfall applies equally to all primitive wrapper types, but we will illustrate it for Integer and int.) When working with Integer objects, it is tempting to use == to compare values, because that is what you would do with int values. And in some cases this will seem to work: Integer int1_1 =...

functions.php //Localize the AJAX URL and Nonce add_action('wp_enqueue_scripts', 'example_localize_ajax'); function example_localize_ajax(){ wp_localize_script('jquery', 'ajax', array( 'url' => admin_url('admin-ajax.php'), 'nonce' => wp_create_nonce('example_ajax_nonc...

public class Singleton { private static class InstanceHolder { static final Singleton INSTANCE = new Singleton(); } public static Singleton getInstance() { return InstanceHolder.INSTANCE; } private Singleton() {} } This initializes the INSTANCE vari...

Getting all the information of current user in wordpress using the predefined function wp_get_current_user(); <?php $current_user = wp_get_current_user(); echo "Username :".$current_user->user_login; echo "Username :".$current_user-&g...

function remove_contact_methods( $contactmethods ) { unset($contactmethods['facebook_profile']); unset($contactmethods['twitter_profile']); return $contactmethods; } add_filter( 'user_contactmethods', 'remove_contact_methods', 10, 1);

A Stream of items that are in turn streamable can be flattened into a single continuous Stream: Array of List of Items can be converted into a single List. List<String> list1 = Arrays.asList("one", "two"); List<String> list2 = Arrays.asList("three&quot...

To create a Grails application, use the grails create-app command. The following command creates a Grails application, named myapp in the current directory: grails create-app fancy-app Running it, is as simple as visiting the, newly created, application directory: cd fancy-app and then grai...

It is sometimes useful to verify that your work on Developer edition hasn't introduced a dependency on any features restricted to Enterprise edition. You can do this using the sys.dm_db_persisted_sku_features system view, like so: SELECT * FROM sys.dm_db_persisted_sku_features Against the datab...

generate sample DF In [39]: df = pd.DataFrame(np.random.randint(0, 10, size=(5, 6)), columns=['a10','a20','a25','b','c','d']) In [40]: df Out[40]: a10 a20 a25 b c d 0 2 3 7 5 4 7 1 3 1 5 7 2 6 2 7 4 9 0 8 7 3 5 8 8 9 6 8 4 8 1 ...

from datetime import datetime import pandas_datareader.data as wb stocklist = ['AAPL','GOOG','FB','AMZN','COP'] start = datetime(2016,6,8) end = datetime(2016,6,11) p = wb.DataReader(stocklist, 'yahoo',start,end) p - is a pandas panel, with which we can do funny things: let's see what...

import os import glob import pandas as pd def get_merged_csv(flist, **kwargs): return pd.concat([pd.read_csv(f, **kwargs) for f in flist], ignore_index=True) path = 'C:/Users/csvfiles' fmask = os.path.join(path, '*mask*.csv') df = get_merged_csv(glob.glob(fmask), index_col=None, use...

You can iterate on the object returned by groupby(). The iterator contains (Category, DataFrame) tuples. # Same example data as in the previous example. import numpy as np import pandas as pd np.random.seed(0) df = pd.DataFrame({'Age': np.random.randint(20, 70, 100), 'Sex':...