Programming Articles - Page 1424 of 3363

The above error means plot is not being created yet hence abline function cannot be used to draw anything on the plot. Therefore, a plot needs to be created first to use abline function for creating a line or any other thing. Mostly, abline is used to create regression line on the plot, thus we need to create a scatterplot first before using abline.Example Live DemoConsider the below data frame −x

To replace a complete column in an R data frame, we can set the original one to new values by using delta operator. For example, if we have a data frame called df that contains a column x which 500 has values from normal distribution then to replace it with the normal distribution having a mean of 25 can be done as df$x

To change the partial plot background, we can create a rectangle using geom_rect function by defining both the axes values and alpha for transparency, the color will be changed by using fill argument. The value of alpha will completely hide the grey background and we can play with its value based on our need.Example Live DemoConsider the below data frame −x

In Data Analysis, we often deal with the comparison of values and this comparison could be also done after finding the closest value to a certain value that might be threshold. For this purpose, we can use filter function of dplyr package along with abs and min function, the abs and min function are required to create the formula for finding the closest value.Consider the below data frame −Example Live DemoCategory

To convert NaN to NA in an R data frame, we can set the NaN values to NA values by using single square brackets. Firstly, we would need to access the column that contains NaN values then NaN values will be accessed using is.nan then we can set those values to NA as shown in the below examples.Consider the below data frame −Example Live Demox1

A dummy variable is a type of variable that takes a value of 1 if the value for which the dummy variable is created exists in the data frame, otherwise it takes 0. Therefore, if we have a one binary variable in a data frame then there will be two dummy variables for the same. To create a dummy variable, we can use model.matrix function as shown in the below examples.Consider the below data frame −Example Live DemoTemp

A binary variable is a type of variable that can take only two possible values like gender that has two categories male and female, citizenship of a country with two categories as yes and no, etc. If the binary variable is not in 0/1 format then it can be converted with the help of ifelse function. Check out the below examples to understand how it works.Consider the below data frame −Example Live DemoTemp

To add an extra point to scatterplot using ggplot2, we can still use geom_point function. We just need to use aes function for quoting with new values for the variables, also we can change the color of this point using colour argument. The display of an extra point will help us to distinguish between a threshold/new value and remaining values.Consider the below data frame −Example Live Demox

To extract words from a string vector, we can use word function of stringr package. For example, if we have a vector called x that contains 100 words then first 20 words can be extracted by using the command word(x,start=1,end=20,sep=fixed(" ")). If we want to start at any other word then starting value will be changed accordingly.Example Live Demox

To find the rate of return for a vector values, we can use the formula for rate of return. For example, if we have a vector called x then the rate of return can be calculated by using the syntax diff(x)/x[-length(x)]. The output will be in decimal form and if we want to convert it to percentage then the output needs to be multiplied with 100, we can also input the same within the formula as (diff(x)/x[-length(x)])*100.Example Live Demox1