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A string vector contains element inside double-quotes and an integer vector does not have any quotes. Sometimes integer values are stored in double-quotes hence the vector of these values is treated as a string vector in R but we need the integer values to perform mathematical operations. Therefore, we can use as.integer function to convert the string vector into an integer vector.Example1Live Demo> x1 x1Output[1] "3" "2" "1" "2" "1" "1" "1" "1" "1" "1" "3" "3" "3" "1" "2" "1" "1" "2" [19] "2" "3" "3" "3" "3" "2" "3" "3" "3" "2" "1" "2" "3" "3" "2" "1" ... Read More
We are required to write a JavaScript function that takes in an array of literal values as the first argument and a string as the second argument.Our function should sort the array alphabetically but keeping the string provided as the second argument (if it exists in the array) as the first element, irrespective of the text it contains.ExampleThe code for this will be −const arr = ["Apple", "Orange", "Grapes", "Pineapple", "None", "Dates"]; const sortKeepingConstants = (arr = [], text = '') => { const sorter = (a, b) => { return (b === text) - (a ... Read More
There are many ways to find the mean of a matrix elements by excluding diagonal elements, this mean is actually the mean of lower triangular matrix and the upper triangular matrix. We can simply use mean function by creating a vector of lower and upper triangular matrix as shown in the below examples.Example1Live Demo> M1 M1Output [, 1] [, 2] [, 3] [, 4] [1, ] 1 6 3 6 [2, ] 8 5 3 4 [3, ] 5 4 4 6 [4, ] 5 5 3 4 ... Read More
Suppose, we have two child and parent JSON arrays of objects like these −const child = [{ id: 1, name: 'somename', parent: { id: 2 }, }, { id: 2, name: 'some child name', parent: { id: 4 } }]; const parent = [{ id: 1, parentName: 'The first', child: {} }, { id: 2, parentName: 'The second', child: {} }, { id: 3, parentName: 'The third', child: {} }, { id: 4, parentName: 'The ... Read More
Suppose we have a sorted array of numbers like this where we can have consecutive numbers.const arr = [1, 2, 3, 5, 7, 8, 9, 11];We are required to write a JavaScript function that takes one such array.Our function should form a sequence for this array. The sequence should be such that for all the consecutive elements of the array, we have to just write the starting and ending numbers replacing the numbers in between with a dash (-), and keeping all other numbers unchanged.Therefore, for the above array, the output should look like −const output = '1-3, 5, 7-9, ... Read More
The bar plot can be easily created with the help of geom_bar. But if we want to have a different border for a particular bar then we first need to create the bar plot and store it in an object. After that we need to add the original plot with the bar for which we want to have a black border. Check out the below example to understand how it can be done.ExampleConsider the below data frame:Live Demo> Group Freq df dfOutput Group Freq 1 G1 18 2 G2 27 3 G3 24Loading ggplot2 ... Read More
The echelon form of a matrix is the matrix that has the following characteristics:1. The first non-zero element in each row, called the leading entry, is 1.2. Each leading entry is in a column to the right of the leading entry in the previous row.3. Rows with all zero elements, if any, are below rows having a non-zero element.In R, we can use echelon function of matlib package to find the echelon form of the matrix.ExampleLive Demo> M MOutput [, 1] [, 2] [, 3] [, 4] [, 5] [1, ] 8 11 3 10 13 [2, ] ... Read More
Suppose, we have an array of objects like this −const arr = [ {"Date":"2014", "Amount1":90, "Amount2":800}, {"Date":"2015", "Amount1":110, "Amount2":300}, {"Date":"2016", "Amount1":3000, "Amount2":500} ];We are required to write a JavaScript function that takes in one such array and maps this array to another array that contains arrays instead of objects.Therefore, the final array should look like this −const output = [ ['2014', 90, 800], ['2015', 110, 300], ['2016', 3000, 500] ];ExampleThe code for this will be −const arr = [ {"Date":"2014", "Amount1":90, "Amount2":800}, {"Date":"2015", "Amount1":110, "Amount2":300}, {"Date":"2016", "Amount1":3000, "Amount2":500} ]; const arrify ... Read More
Suppose, we have a comma-separated string like this −const str = "a, b, c, d , e";We are required to write a JavaScript function that takes in one such and sheds it off all the whitespaces it contains.Then our function should split the string to form an array of literals and return that array.ExampleThe code for this will be −const str = "a, b, c, d , e"; const shedAndSplit = (str = '') => { const removeSpaces = () => { let res = ''; for(let i = 0; i < str.length; ... Read More
Sometimes data is incorrectly entered into systems and that is the reason we must be careful while doing data cleaning before proceeding to analysis. A data collector or the sampled unit might enter blank to an answer if he or she does not find an appropriate option for the question. This also happens if the questionnaire is not properly designed or blank is filled by mistake. Also, if we have categorical variable then a control category might be filled with blank or we may want to have a blank category to use a new one at later stage. Whatever the ... Read More