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To find the percentage for frequencies stored in a vector with two decimal places can be done with the help of sum function and round function. For example, if we have a vector of frequencies say x then the percentage of these frequencies can be found by using the command round((x/sum(x))*100,2). Check out the below examples to understand how it works.Example1Frequency1
If we have factor columns in an R data frame then we want to find the frequency of each factor level for all the factor columns. This can be done with the help of sapply function with table function. For example, if we have a data frame called df that contains some factor columns then the frequency table for factor columns can be created by using the command sapply(df, table).Example1Consider the below data frame −> x1 x2 df1 df1Output x1 x2 1 D a 2 D b 3 D c 4 D b 5 D c 6 C a 7 ... Read More
To set the text position using geom_text, we can use the value for the X-axis and Y-axis with appropriate positions. We need to make sure that the values we set for both the axes do not lie within the data otherwise the text will be printed on the plot we want to draw and it will become less attractiveExampleConsider the below data frame −x
To create a date vector with randomization, we can use sample function but the dates need to be read with as.Date function. For example, if we have 2 dates say 2021-01-01 and 2021-02-02 then a vector with randomization of these three dates can be created by using the command −sample(c(as.Date("2021-01-01"),as.Date("2021-02-02")),100,replace=TRUE)Example1Date1
If we have a character column in the data frame that contains string as well as numeric values and the first digit of the numeric values has some meaning that can help in data analysis then we can extract those first digits. For this purpose, we can use stri_extract_first function from stringi package.Example1Consider the below data frame −> x1 y1 df1 df1Output x1 y1 1 1 HT14L 2 2 HT14L 3 3 HT23L 4 4 HT14L 5 5 HT32L 6 6 HT32L 7 7 ... Read More
Most of the times we need to deal with missing values in data science projects and these missing values can be occurred at any position. We might want to change the position of these missing values and send them to the end of the columns in the data frame. This can be done with the help of lapply function as shown in the below examples.Example1Consider the below data frame −> x1 x2 x3 df1 df1Output x1 x2 x3 1 0 0 2 2 1 1 NA 3 1 NA 0 4 0 NA 2 5 1 NA 2 6 NA ... Read More
To find the index of the nearest smallest number in an R data frame column, we can use which function along with subsetting for the value for which we want to find the index of the nearest smallest number. To understand how it can be done check out the below examples.Example1Consider the below data frame −ID
To convert an old data frame to a new data frame, we can simply set the new name. For example, if we have a data frame called df and want to convert it to a new one let’s say df_new then it can be done as df_new x1 x2 df1 df1Output x1 x2 1 8 6 2 4 9 3 3 2 4 3 5 5 7 4 6 4 8 7 8 6 8 12 12 9 8 6 10 ... Read More
To create a data frame column with letters of both sizes, we can simply use the letters function and LETTERS function, the first one corresponds to lowercase letters and the latter corresponds to uppercase letters with single square brackets as shown in the below examples.Example1df1
Example − In the given tree, the root node is 1, the root of its left sub tree is 2, and the root of its right sub tree is 3, ... so on.Preorder Tree Traversal Output: 1, 2, 4, 5, 3, 6, 7.Approach to solve this problemStep 1 − First, we’ll define the node structure.Step 2 − In the main method, we would create the above tree.Step 3 − Finally, we will perform the Preorder Tree Traversal.Examplepackage main import "fmt" type Node struct { data int left *Node right *Node } func (root *Node)PreOrderTraversal(){ if root ... Read More