Underscore.js _.pick() function is used to return a copy of the object that is filtered using the given key. This function accepts a predicate indicating which keys are picked from the object....

Underscore.js _.reduce() function is an inbuilt function in Underscore.js that is used to transform an array’s/object’s properties into one single value or is used to create a single result from a given list of values. When all the elements of the list are passed to the function/iterate and no more elements remain then the _.each loop ends. The iterate function makes use of memorization, i.e. it remembers the return value each time it calculates a value....

Underscore.js _.findWhere() function is used to have a list of all the elements that match the given property. The _.findWhere() function is used to search a content in the whole list of sections. The section which contains the content will be displayed....

Underscore.js _.where() function is used to find all the elements that match the searching condition. Suppose to find all the student details of a class then apply the _.where() function to the list of all the sections and pass the condition as the section name. So, the names of all the students in that specific section will be displayed....

Underscore.js _.flatten() function is an inbuilt function in the Underscore.js library of JavaScript that is used to flatten an array that is nested to some level. The resultant array will have no depth. It will be completely flattened. If pass the shallow parameter then the flattening will be done only till one level. The depth of an array is given by the number of square brackets. Example: array[10, [20]] contains 10 elements of 1 depth as it is inside only a single bracket ([]) whereas the element 20 has depth 2....

Underscore.js _.debounce() Function in Underscore.js is used to create a debounced function that is used to delay the execution of the given function until after the given wait time in milliseconds has passed since the last time this function was called. The debounced function has a cancel method that can be used to cancel the function calls that are delayed and a flush method which is used to immediately call the delayed function....

Underscore.js _.merge() method merges two or more objects starting with the left-most to the rightmost to create a parent mapping object....

Underscore.js _.once function is used in conditions where we want a particular function to be executed only a single time. Even though we execute or call this function multiple times then also it will have no effect. The original function’s values will only be returned each time it is called. It is mostly used for the initialize() functions which are used to assign only the initial values to the variables....

Underscore.js  _.first() function is used to return the first element of the array, i.e. the number at the zeroth index. It returns the first n elements in the array of m size (n < m) by just passing the variable n in the array. It is a very easy-to-use function of the underscore.js library and is used widely when working with array elements....

Underscore.js _.difference() function returns the values of the array that are not present in the other arrays. If the element is present in the array then this element will not be included in the resultant array. This is because it takes a difference between the second array and the first array....

Underscore.js _.chain() function is an inbuilt function in the Underscore.js library of JavaScript which is used to find a wrapped object. Moreover, invoking the methods on this object will continue to return the wrapped objects until the value is invoked....

Underscore.js _.isNumber() function is used to check whether the given object parameter is a number or not. If the given object is a number then it returns True value otherwise, it returns False....