Tutorial by Examples: u

Matrix multiplication can be done in two equivalent ways with the dot function. One way is to use the dot member function of numpy.ndarray. >>> import numpy as np >>> A = np.ones((4,4)) >>> A array([[ 1., 1., 1., 1.], [ 1., 1., 1., 1.], [ 1., 1.,...

The dot function can also be used to compute vector dot products between two one-dimensional numpy arrays. >>> v = np.array([1,2]) >>> w = np.array([1,2]) >>> v.dot(w) 5 >>> np.dot(w,v) 5 >>> np.dot(v,w) 5

The numpy dot function has an optional parameter out=None. This parameter allows you to specify an array to write the result to. This array must be exactly the same shape and type as the array that would have been returned, or an exception will be thrown. >>> I = np.eye(2) >>> I ...

Since functions are ordinary values, there is a convenient syntax for creating functions without names: List.map (fun x -> x * x) [1; 2; 3; 4] (* - : int list = [1; 4; 9; 16] *) This is handy, as we would otherwise have to name the function first (see let) to be able to use it: let square x...

const int a = 0; /* This variable is "unmodifiable", the compiler should throw an error when this variable is changed */ int b = 0; /* This variable is modifiable */ b += 10; /* Changes the value of 'b' */ a += 10; /* Throws a compiler error */ The const qualif...

If while working you realize you're on wrong branch and you haven't created any commits yet, you can easily move your work to correct branch using stashing: git stash git checkout correct-branch git stash pop Remember git stash pop will apply the last stash and delete it from the stash list. T...

process.argv is an array containing the command line arguments. The first element will be node, the second element will be the name of the JavaScript file. The next elements will be any additional command line arguments. Code Example: Output sum of all command line arguments index.js var sum = 0...

A whole circle is 360 degrees or Math.PI * 2 radians. Half of those values follows to be 180 degrees or Math.PI radians. A quarter is then 90 degrees or Math.PI / 2 radians. To get a segment as a percentage of a whole circle in radians: function getSegment(percent:Number):Number { retur...

Prerequesites Grunt requires Node.js and npm to be installed. If you don’t have Node.js and/or npm installed on your machine, go to https://nodejs.org and download the installer or package for your operating system. First-time install If you're installing Grunt for the first time, you'll first ha...

clojure.spec/and & clojure.spec/or can be used to create more complex specs, using multiple specs or predicates: (clojure.spec/def ::pos-odd (clojure.spec/and odd? pos?)) (clojure.spec/valid? ::pos-odd 1) ;;=> true (clojure.spec/valid? ::pos-odd -3) ;;=> false or works similarl...

spec can describe and be used with arbitrary sequences. It supports this via a number of regex spec operations. (clojure.spec/valid? (clojure.spec/cat :text string? :int int?) ["test" 1]) ;;=> true cat requires labels for each spec used to describe the sequence. cat describes a seq...

Sometimes you may only need to simulate an event with two outcomes, maybe with different probabilities, but you may find yourself in a situation that calls for many possible outcomes with different probabilities. Let's imagine you want to simulate an event that has six equally probable outcomes. T...

Consider a production table called questions_mysql and a table iwtQuestions (imported worktable) representing the last batch of imported CSV data from a LOAD DATA INFILE. The worktable is truncated before the import, the data is imported, and that process is not shown here. Update our production da...

A While loop starts by evaluating a condition. If it is true, the body of the loop is executed. After the body of the loop is executed, the While condition is evaluated again to determine whether to re-execute the body. Dim iteration As Integer = 1 While iteration <= 10 Console.Writeline(ite...

2.3-2.3.2 An enclosing CoordinatorLayout can be used to achieve Material Design Scrolling Effects when using inner layouts that support Nested Scrolling, such as NestedScrollView or RecyclerView. For this example: app:layout_scrollFlags="scroll|enterAlways" is used in the Toolbar pro...

Sometimes, you have to create two Disposable objects in a row. There is an easy way to avoid nesting Using blocks. This code Using File As New FileStream("MyFile", FileMode.Append) Using Writer As New BinaryWriter(File) 'You code here Writer.Writer("Hello&quot...

Place your test classes here: /src/test/<pkg_name>/ Example test class public class ExampleUnitTest { @Test public void addition_isCorrect() throws Exception { int a=4, b=5, c; c = a + b; assertEquals(9, c); // This test passes assertEquals(10, c...

A slider element can have its value set on initialization by providing a value option. This option is a number: $( "#slider" ).slider({ value: 5 }); A range slider can also have its values set in this way by providing a values option. This option is an array of numbers: $( &qu...

The slider provides an event called slide that will trigger whenever the mouse moves during a slider handle drag. This function holds a reference to the slide event and a reference to the slider ui object. The ui object holds a jQuery object for the handle being moved and the value(s) of the slide...

The slider provides an event called change that will trigger after the mouse completes a slider handle drag or if the value(s) have been changed programmatically. This function holds a reference to the slide event and a reference to the slider ui object. The ui object holds a jQuery object for the ...