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To create a line chart with 3-sigma limits using ggplot2, we first need to calculate the limits then the chart can be created. We can use geom_ribbon function of ggplot2 for this purpose where we can pass lower 3-sigma limit for ymin argument in aes and upper 3-sigma limit for ymin argument in aes, also we need to specify alpha so that the color of lines and the limits can be differentiated.ExampleConsider the below data frame:> set.seed(14) > x y df dfOutput x y 1 1 0.6690751 2 2 1.8594771 3 3 ... Read More
We are given a number N as input. The goal is to find all N digit numbers that have an even number of 0’s as digits. The number also could have preceding zeros like in case of N=3 numbers included will be 001, 002, 003….010….so on.Let us understand with examples.Input − N=4Output − Count of no. with N digits which consists of even number of 0's are − 7047Explanation − All 4 digits numbers would be like −Smallest will be 0000, then 0011, 0012, 0013, 0014…..Highest will be 9900.Input − N=5Output − Count of no. with N digits which consists ... Read More
There are many small objectives that helps us to achieve a greater objective in data analysis. One such small objective is checking if a value exists in the data set or not. In R, we have many objects for data set such as data frame, matrix, data.table object etc. If we want to check if a value exists in an R data frame then any function can be used.ExampleConsider the below data frame:> set.seed(3654) > x1 x2 x3 x4 df1 df1Output x1 x2 x3 x4 1 4 5 16 2 2 5 4 15 ... Read More
We are given a number N as input. The goal is to find all N digit numbers that have an odd number of 0’s as digits. The number also could have preceding zeros like in case of N=3 numbers included will be 000, 011, 012….990.Let us understand with examples.Input − N=3Output − Count of no. with N digits which consists of even number of 0's are − 244Explanation − All 3 digit numbers would be like −Smallest will be 000, then 011, 012, 013, 0014…..Highest will be 990.Input − N=5Output − Count of no. with N digits which consists of ... Read More
We are given with two strings str_1 and str_2 as input. The goal is to find the count of strings same as str_2 that can be constructed using letters picked from str_1 from which each character is used just once.Note − All alphabets in both are in the same case.Let us understand with examples.Input − str_1 = "abcaaaabca", str_2 = "bca";Output − Count occurrences of a string that can be constructed from another given string are: 2Explanation − Substrings bca in str_a −str_1[1-3]=”bca” and str[7-9]=”bca”Input − str_1 = "about", str_2 = "cout";Output − Count occurrences of a string that can ... Read More
A contingency table is a cross-tabulation that looks like a matrix. These tables can have different as well as equal number of columns and rows. If we want to create a contingency table using datasets in base R then table function can be used. For example, if we want to create a contingency table for cyl and gear column of mtcars data then it can be done as shown in the below example 1.Example1> head(mtcars)Outputmpg cyl disp hp drat wt qsec vs am gear carb Mazda RX4 21.0 6 160 110 3.90 2.620 16.46 0 1 4 4 Mazda RX4 ... Read More
We are given string str containing 0’s, 1’s, and 2’s only. The goal is to find all substrings of str that have equal numbers of 0’s 1’s and 2’s. If str is “12012”. Substrings with equal 0’s, 1’s, and 2’s will be “120”, “201” and “012”. The count will be 3.Let us understand with examples.Input − str=”112200120”Output −Count of Substrings with an equal number of 0s, 1s, and 2s are − 5Explanation − Substrings will bestr[0-5]=”112200”, str[1-6]=”122001”, str[5-7]=”012”, str[6-8]=”120”, str[7-0]=”201”Input − str=”12012”Output −Count of Substrings with an equal number of 0s, 1s, and 2s are: 3Explanation − Substrings will be ... Read More
If we have a confusion matrix then the sensitivity and specificity can be calculated using confusionMatrix function of caret package. For example, if we have a contingency table named as table then we can use the code confusionMatrix(table). This will return sensitivity and specificity as well as many other metrics.Example1> x1 y1 table1 table1Outputy1 x1 a b c d a 0 0 1 0 b 0 1 2 1 c 2 2 0 2 d 3 2 1 3Loading caret package:> library(caret)Finding sensitivity and specificity of table1:> confusionMatrix(table1)Confusion Matrix and StatisticsOutputy1 x1 a b c d ... Read More
We are given a string str. The goal is to count the number of substrings in str that have the same starting and ending character. For example, if input is “baca” substrings will be “b”, “a”, “c”, “a”, “aca”. Total 5.Let us understand with examples.Input − str=”abaefgf”Output −Count of substrings with same first and last characters are: 9Explanation − Substrings will be“a”, “b”, “a”, “e” ,”f”, “g”, “f”, “aba”, “fgf”. Total 9.Input − str=”abcdef”Output −Count of substrings with same first and last characters are: 6Explanation − Substrings will be −“a” , “b” , “c”, “d”, “e” ,”f”. Total 6The approach ... Read More
We are given a string str. The goal is to count the number of substrings in str that have each character occurring utmost k times. For example if input is “abc” and k=1, the substrings will be “a”, “b”, “c”, “ab”, “bc”, “abc”.Let us understand with examples.Input − str=”abaefgf”Output − Count of substrings with same first and last characters are &mmius; 9Explanation − Substrings will be“a”, “b”, “a”, “e” ,”f”, “g”, “f”, “aba”, “fgf”. Total 9.Input − str=”abcdef”Output − Count of substrings with same first and last characters are: 6Explanation − Substrings will be -“a” , “b” , “c”, “d”, ... Read More