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We are required to write a JavaScript function that takes in an array that contains elements of different data types and the function should return a map representing the frequency of each data type.Let’s say the following is our array −const arr = [23, 'df', undefined, null, 12, { name: 'Rajesh' }, [2, 4, 7], 'dfd', null, Symbol('*'), 8];ExampleFollowing is the code to return a map representing the frequency of each datatype −const arr = [23, 'df', undefined, null, 12, { name: 'Rajesh' }, [2, 4, 7], 'dfd', null, Symbol('*'), 8]; const countDataTypes = arr => { ... Read More
We are required to write a JavaScript function that takes in two arrays of numbers. And the function should return true if the two arrays upon combining and shuffling can form a consecutive sequence, false otherwise.For example: If the arrays are −const arr1 = [4, 6, 2, 9, 3]; const arr2 = [1, 5, 8, 7];Then the output should be true.Therefore, let’s write the code for this function −ExampleThe code for this will be −const arr1 = [4, 6, 2, 9, 3]; const arr2 = [1, 5, 8, 7]; const canFormSequence = (arr1, arr2) => { const combined = ... Read More
We are required to write a JavaScript function that takes in a string sentence as first and the only argument. And the function should return the length of the second smallest word from the string.For example: If the string is −const str = 'This is a sample string';Then the output should be 2.Therefore, let’s write the code for this function −ExampleThe code for this will be −const str = 'This is a sample string'; const secondSmallest = str => { const strArr = str.split(' '); if(strArr.length < 2){ return false; } for(let i ... Read More
We are required to write a JavaScript function that takes in a string as the first argument, a number, say n, as the second argument and a character, say c, as the third argument. The function should replace the nth appearance of any character with the character provided as the third argument and return the new string.Therefore, let’s write the code for this function −ExampleThe code for this will be −const str = 'This is a sample string'; const num = 2; const char = '*'; const replaceNthAppearance = (str, num, char) => { const creds = str.split('').reduce((acc, val, ... Read More
We are required to write a JavaScript function that takes in an array of numbers and returns a subarray that contains all the element from the original array that are larger than all the elements on their right.Therefore, let’s write the code for this function −ExampleThe code for this will be −const arr = [12, 45, 6, 4, 23, 23, 21, 1]; const largerThanRight = (arr = []) => { const creds = arr.reduceRight((acc, val) => { let { largest, res } = acc; if(val > largest){ res.push(val); largest = val; }; return { largest, res }; }, { largest: -Infinity, res: [] }); return creds.res; }; console.log(largerThanRight(arr));OutputThe output in the console will be −[ 1, 21, 23, 45 ]
A string can be considered as a valid hex code if it contains no characters other than the 0-9 and a-f alphabets.For example:'3423ad' is a valid hex code '4234es' is an invalid hex codeWe are required to write a JavaScript function that takes in a string and checks whether its a valid hex code or not.ExampleThe code for this will be −const str1 = '4234es'; const str2 = '3423ad'; const isHexValid = str => { const legend = '0123456789abcdef'; for(let i = 0; i < str.length; i++){ if(legend.includes(str[i])){ continue; ... Read More
The default graph created by using ggplot2 package shows the axes labels depending on the starting and ending values of the column of the data frame or vector but we might want to visualize it just like we do in paper form of graphs that shows all of the four quadrants. This can be done by using xlim, ylim, geom_hline, and geom_vline functions with ggplot function of ggplot2 package.Consider the below data frame −Example Live Demox
Subsetting can be required in many different ways, we can say that there might be infinite number of ways for subsetting as it depends on the objective of the bigger or smaller analysis. One such way is subsetting a matrix based on a certain value of column of the matrix. In R, we can easily do the same with the help of subset function as shown in below example.Example Live DemoM3)Output [,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9] [,10] [1,] 4 14 24 34 44 54 64 74 84 94 [2,] 5 15 25 35 45 55 65 75 85 95 [3,] 6 16 26 36 46 56 66 76 86 96 [4,] 7 17 27 37 47 57 67 77 87 97 [5,] 8 18 28 38 48 58 68 78 88 98 [6,] 9 19 29 39 49 59 69 79 89 99 [7,] 10 20 30 40 50 60 70 80 90 100Examplesubset(M,M[,1]75)Output[,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9] [,10] [1,] 6 16 26 36 46 56 66 76 86 96 [2,] 7 17 27 37 47 57 67 77 87 97 [3,] 8 18 28 38 48 58 68 78 88 98 [4,] 9 19 29 39 49 59 69 79 89 99 [5,] 10 20 30 40 50 60 70 80 90 100Examplesubset(M,M[,9]>81)Output[,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9] [,10] [1,] 2 12 22 32 42 52 62 72 82 92 [2,] 3 13 23 33 43 53 63 73 83 93 [3,] 4 14 24 34 44 54 64 74 84 94 [4,] 5 15 25 35 45 55 65 75 85 95 [5,] 6 16 26 36 46 56 66 76 86 96 [6,] 7 17 27 37 47 57 67 77 87 97 [7,] 8 18 28 38 48 58 68 78 88 98 [8,] 9 19 29 39 49 59 69 79 89 99 [9,] 10 20 30 40 50 60 70 80 90 100Examplesubset(M,M[,9]
The anti-diagonal elements in a matrix are the elements that form straight line from right upper side to right bottom side. For example, if we have a matrix as shown below −1 2 3 4 5 6 7 8 9then the diagonal elements would be 1, 5, 9 and the anti-diagonal elements would be 3, 5, 7.To find the sum of these anti-diagonal elements, we can use apply function.Example Live DemoM1
It is common the find the correlation coefficient between columns of an R data frame but we might want to find the correlation coefficient between rows of two data frames. This might be needed in situations where we expect that there exists some relationship row of an R data frame with row of another data frame. For example, row of an R data frame showing buying trend of a customer in one year and the same row of the other data frame showing buying trend of the same customer in another year.Consider the below data frame −Example Live Demox1Read More