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raw_data = {'first_name': ['John', 'Jane', 'Jim'], 'last_name': ['Doe', 'Smith', 'Jones'], 'department': ['Accounting', 'Sales', 'Engineering'],} df = pd.DataFrame(raw_data,columns=raw_data.keys()) df.to_csv('data_file.csv')

This is a very common Exception. It causes your application to stop during the start or execution of your app. In the LogCat you see the message: android.content.ActivityNotFoundException : Unable to find explicit activity class; have you declared this activity in your AndroidManifest.xml? In ...

The cx and cy values designate the location of the center of the circle. The r attribute specifies the size of the radius of the circle. <svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"> <circle cx="40" cy="40&q...

class Car { public position: number = 0; private speed: number = 42; move() { this.position += this.speed; } } In this example, we declare a simple class Car. The class has three members: a private property speed, a public property position and a public met...

class Car { public position: number = 0; protected speed: number = 42; move() { this.position += this.speed; } } class SelfDrivingCar extends Car { move() { // start moving around :-) super.move(); super.move(); } } ...

public class Singleton { private static final Singleton INSTANCE = new Singleton(); private Singleton() {} public static Singleton getInstance() { return INSTANCE; } } It can be argued that this example is effectively lazy initialization. Section 12.4.1 of ...

To increment date objects in Javascript, we can usually do this: var checkoutDate = new Date(); // Thu Jul 21 2016 10:05:13 GMT-0400 (EDT) checkoutDate.setDate( checkoutDate.getDate() + 1 ); console.log(checkoutDate); // Fri Jul 22 2016 10:05:13 GMT-0400 (EDT) It is possible to use setD...

To implement an item click listener and/or an item long click listener, you can create an interface in your adapter: public class CustomAdapter extends RecyclerView.Adapter<CustomAdapter.ViewHolder> { public interface OnItemClickListener { void onItemSeleted(int position, Vi...

countMatches method from org.apache.commons.lang3.StringUtils is typically used to count occurences of a substring or character in a String: import org.apache.commons.lang3.StringUtils; String text = "One fish, two fish, red fish, blue fish"; // count occurrences of a substring Str...

Start with an iterable which needs to be grouped lst = [("a", 5, 6), ("b", 2, 4), ("a", 2, 5), ("c", 2, 6)] Generate the grouped generator, grouping by the second element in each tuple: def testGroupBy(lst): groups = itertools.groupby(lst, key=lambda...

HTML <p>My shadow always follows me.</p> CSS p { -webkit-filter: drop-shadow(10px 10px 1px green); filter: drop-shadow(10px 10px 1px green); } Result

To use multiple filters, separate each value with a space. HTML <img src='donald-duck.png' alt='Donald Duck' title='Donald Duck' /> CSS img { -webkit-filter: brightness(200%) grayscale(100%) sepia(100%) invert(100%); filter: brightness(200%) grayscale(100%) sepia(100%) invert(1...

HTML <div></div> CSS div { width: 100px; height: 100px; background-color: white; -webkit-filter: invert(100%); filter: invert(100%); } Result Turns from white to black.

A Bootstrap carousel is a Bootstrap component that creates a slideshow which cycles through elements within the carousel. Here is a basic HTML usage example: <div id="carousel-example-generic" class="carousel slide" data-ride="carousel"> <!-- Indicators --...

Carousel components can be instantiated via jQuery with the function $('.carousel').carousel(options), where $('.carousel') is a top-level reference to the specific carousel and options is a Javascript object specifying the carousel's default attributes. The options object allows for multiple prope...

using System; using Xamarin.Forms; namespace NavigationApp { public class App : Application { public App() { MainPage = new NavigationPage(new FirstPage()); } } public class FirstPage : ContentPage { Label FirstPage...

Generally you should avoid using the default database role (often postgres) in your application. You should instead create a user with lower levels of privileges. Here we make one called niceusername and give it a password very-strong-password CREATE ROLE niceusername with PASSWORD 'very-strong-pas...

If we want to iterate backwards through a list or vector we can use a reverse_iterator. A reverse iterator is made from a bidirectional, or random access iterator which it keeps as a member which can be accessed through base(). To iterate backwards use rbegin() and rend() as the iterators for the e...

The arc4random_uniform() function is the simplest way to get high-quality random integers. As per the manual: arc4random_uniform(upper_bound) will return a uniformly distributed random number less than upper_bound. arc4random_uniform() is recommended over constructions like ''arc4random() % uppe...

The following code demonstrates usage of arc4random_uniform() to generate a random integer between 3 and 12: uint32_t randomIntegerWithinRange = arc4random_uniform(10) + 3; // A random integer between 3 and 12 This works to create a range because arc4random_uniform(10) returns an integer between...