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Assignment 25 CB - Arith Geo

Have the function arithGeo(arr) take the array of numbers stored in arr and return the string "Arithmetic" if the sequence follows an arithmetic pattern or return "Geometric" if it follows a geometric pattern. If the sequence doesn't follow either pattern return -1. An arithmetic sequence is one where the difference between each of the numbers is consistent, where as in a geometric sequence, each term after the first is multiplied by some constant or common ratio. Arithmetic example: [2, 4, 6, 8] and Geometric example: [2, 6, 18, 54]. Negative numbers may be entered as parameters, 0 will not be entered, and no array will contain all the same elements.

Enter some numbers, separated by comma, in the field below.

$(document).ready(function() { function getArray(element) { element = element.split(','); element = element.map(function(current, index, element) { return current.trim(); }); return element; // Returns trimmed array } function arithGeo(arr) { var arithFactor = arr[1] - arr[0], geomFactor = arr[1] / arr[0], message = 'Arithmetic', len = arr.length, i; for (i = 0; i < len - 1; i++) { if (arithFactor === arr[i + 1] - arr[i] && message === 'Arithmetic') { // First check if it is arithmetic message = 'Arithmetic'; } else message = 'Geometric'; // If not, assum it is geometric } for (i = 0; i < len - 1; i++) { if (geomFactor === arr[i + 1] / arr[i] && message === 'Geometric') { // Check if it is geometric message = 'Geometric'; } else if (message !== 'Arithmetic') { // If not, and not arithmetic, then return -1 message = -1; }; } return message; } $('.check').click(function() { var element = $('.data input').val(), message = ''; if (element === '') { message = 'Please enter a string in the field.'; } else { message = 'Array is: <span>' + arithGeo(getArray(element)) + '</span>'; } $('.result p ').html(message); }); });