const oTestArray = [{ width: 200 }];
for (let i = 0; i < 5; i++) {
oTestArray.push({ width: 100 });
}
console.log(oTestArray);
const oTestArray = [];
oTestArray.push("Udo", "Ede");
console.log(oTestArray);
import numpy as np from numpy.random import rand from numpy.linalg import solve, inv # Vektor a = np.array([1, 2, 3, 5]) # Vektor mit äquidistanten Werten erzeugen b = np.linspace(0, 2, 4) print(a) print(b) # Vektor generieren v = np.linspace(-np.pi, np.pi, 10) vs = np.sin(v) vc = np.cos(v) print(v) print(vs) print(vc) # Matrix c = np.array([[1, 2, 3], [3, 4, 5], [6, 7, 8]]) # transponieren d = c.transpose() # invertieren e = inv(c) print(d) print(e)
let arr_col = new Array('rot', 'grün', 'blau');
console.log(arr_col.length);
let arr_col = new Array('rot', 'grün', 'blau');
console.log(arr_col.indexOf('grün'));
let arr_col = new Array('rot', 'grün', 'blau');
// ", " als Separatorzeichen
console.log(arr_col.join(", "));
// Definition let language = new Array(); language["DE"] = "Guten Morgen"; language["EN"] = "Good morning"; language["IT"] = "Buongiorno"; language["FR"] = "Bonjour"; // Guten Morgen User! console.log(language["DE"] + " " + "User!"); // ["DE","EN","IT","FR"] var aKeys = Object.keys(language); console.log(JSON.stringify(aKeys)); // 12 console.log(language["DE"].length); // 0 console.log(language.length);
// Definition let language = new Object(); language["DE"] = "Guten Morgen"; language["EN"] = "Good morning"; language["IT"] = "Buongiorno"; language["FR"] = "Bonjour"; // Guten Morgen User! console.log(language["DE"] + " " + "User!"); // ["DE","EN","IT","FR"] var aKeys = Object.keys(language); console.log(JSON.stringify(aKeys)); // 12 console.log(language["DE"].length); // undefined console.log(language.length);
// Alter, nach dem das Personenarray gefiltert werden soll
let filter_age = 60;
// Array mit Namen und Alter
let arr_persons = [ { name:"Horst", age:50 },
{ name:"Udo", age:55 },
{ name:"Heinz", age:60 },
{ name:"Ede", age:65 } ];
// neues, gefiltertes Array
let arr_filtered = arr_persons.filter( function(p){
return p.age >= filter_age;
} );
// Ausgabe des gefilterten Arrays
arr_filtered.forEach(function(p){
console.log(p.name + ": " + p.age);
});
// Variante 1
class Car {}
class Audi extends Car {}
let a = new Audi();
console.log(a instanceof Car);
// Variante 2
let arr = [1, 2, 3];
console.log(arr instanceof Object);
console.log(arr instanceof Array);
// Klasse Array erweitern
class Stack extends Array {
get first() {
return this[0];
}
get last() {
return this[this.length - 1];
}
}
var stack = new Stack();
stack.push('Udo');
stack.push('Horst');
// Udo
console.log(stack.first);
// Horst
console.log(stack.last);
// https://www.w3schools.com/jsref/jsref_sort.asp
// einfaches Sortieren
let arr = ['rot', 'grün', 'blau'];
arr.sort();
console.log(arr);
// über compare-Funktion sortieren
let arr = [20, 10, 1, 4, 8, 70];
// aufsteigend
arr.sort(function(a, b) { return a-b; } );
console.log(arr);
let arr = [20, 10, 1, 4, 8, 70];
// absteigend
arr.sort(function(a, b) { return b-a; } );
console.log(arr);