Take Subset of Matrix in R with Finite Values

Nizamuddin Siddiqui
Updated on 10-Oct-2020 12:50:52

427 Views

If we have a matrix that contains NA or Inf values and we want to take the subset of that matrix with finite values then only the rows that do not contain NA or Inf values will be the output. We can do this in R by using rowSums and is.finite function with negation operator !.Example Live Demoset.seed(999) M1

Find Index of Last Occurrence of Repeated Values in a Vector in R

Nizamuddin Siddiqui
Updated on 10-Oct-2020 12:41:25

585 Views

Indexing helps us to understand the location of the value in the vector. If we have a vector that contains repeated values then we might want to figure out the last occurrence of the repeated value. For example, if we have a vector x that contains 1, 1, 2, 1, 2 then the last occurrence of repeated values will be 4 and 5 because the last 1 is at 4th position and 2 is at the 5th position. We can find this by using tapply function in R.Example Live Demox1

Join Points in a Point Chart with Lines Using ggplot2 in R

Nizamuddin Siddiqui
Updated on 10-Oct-2020 12:35:08

604 Views

Usually, a point chart is created to assess the relationship or movement of two variables together but sometimes these points are scattered in a way that makes confusion. Hence, data analyst or researcher try to visualize this type of graph by joining the points with lines. In ggplot2, this joining can be done by using geom_line() function.Consider the below data frame −Example Live Demoset.seed(111) x

Generate Normal Random Vector Using Mean of a Vector in R

Nizamuddin Siddiqui
Updated on 10-Oct-2020 12:32:07

1K+ Views

To create a normal random vector, we can use rnorm function with mean and standard deviation as well as without passing these arguments. If we have a different vector derived from another distribution or simply represent some numbers then we can use the mean of that vector in the rnorm function for mean argument.Example Live Demoset.seed(101) x1

Find Prime Numbers Between Two Values or Up to a Value in R

Nizamuddin Siddiqui
Updated on 10-Oct-2020 12:30:22

1K+ Views

We know that the prime numbers are the numbers that are not divisible by any number except by themselves or 1 and 1 is not considered as a prime number. In R, we can find the prime numbers up to a number or between two numbers by using Prime function of numbers package. If we want to find the total number of prime numbers between 1 and 10, then we just need to pass 10 inside the Prime function, otherwise range will be required.Loading numbers package −library("numbers")Primes(10)[1] 2 3 5 7Primes(100)[1] 2 3 5 7 11 13 17 19 23 ... Read More

Difference Between Regression Line and Points in R

Nizamuddin Siddiqui
Updated on 10-Oct-2020 12:28:47

299 Views

The difference between regression line and the points on the scatterplot are actually the residuals, thus we need to calculate the residual from the model object. This can be simply done by using residuals function. For example, if we create a linear model defined as Model between x and y then the residuals will be found as residuals(Model).Consider the below data frame −Example Live Demoset.seed(999) x1

Convert Rows in an R Data Frame to List

Nizamuddin Siddiqui
Updated on 10-Oct-2020 12:18:07

2K+ Views

Sometimes each row needs to be treated differently, therefore, we might want to convert those rows into list. This will help us to perform the operations on our row elements separately. To convert the rows into list, we can use split function by defining the number of rows in the data frame.Consider the below data frame −Example Live Demoset.seed(101) x1

Find Length of Longest Common Substring in C++

Arnab Chakraborty
Updated on 10-Oct-2020 12:15:42

2K+ Views

Suppose we have two lowercase strings X and Y, we have to find the length of their longest common substring.So, if the input is like X = "helloworld", Y = "worldbook", then the output will be 5, as "world" is the longest common substring and its length is 5.To solve this, we will follow these steps −Define an array longest of size: m+1 x n+1.len := 0for initialize i := 0, when i

Combine Two Matrices to Create a Block Diagonal Matrix in R

Nizamuddin Siddiqui
Updated on 10-Oct-2020 12:10:13

912 Views

A block-diagonal matrix means that a matrix added to another matrix at the end the last element. For example, if we have a matrix with nine values and the other matrix also has nine values then the second matrix will be added to the first matrix and the elements below first matrix will be zero and the elements above the second matrix will also be zero.Example Live DemoM1

Find Length of Longest Common Subsequence in C++

Arnab Chakraborty
Updated on 10-Oct-2020 12:05:58

269 Views

Suppose we have two strings text1 and text2, we have to find the length of their longest common subsequence. As we know a subsequence of a string is a new string generated from the original string with some characters deleted without changing the relative order of the remaining characters. (So for example "abe" is a subsequence of "abcde" but "adc" is not). A common subsequence of two strings is a subsequence that is common to both strings. So If there is no common subsequence, return 0. If the input is like “abcde”, and “ace”, then the result will be 3.To ... Read More

Advertisements