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Nizamuddin Siddiqui has Published 2307 Articles

Nizamuddin Siddiqui
126 Views
When two categorical variables make an impact on the response variable together then it is necessary to visualize their effect graphically because this graph helps us to understand the variation in the effect. Therefore, we can create a plot for the response variable that changes with one or both of ... Read More

Nizamuddin Siddiqui
2K+ Views
A matrix can have multiple rows and columns like a data frame. As in data frames, we sometimes require to take subsets, the same might be required with matrices. But subsetting matrices data is quite simple as compared to subsetting a data frame.ExampleConsider the below matrix −> M M [, ... Read More

Nizamuddin Siddiqui
566 Views
When there is a common factor with different levels, the joining of data frames is possible but the result will present all the levels with dplyr. We can make use of left_join function to join the two data frames but the size of the first data frame must be greater ... Read More

Nizamuddin Siddiqui
617 Views
Selection of top or bottom elements can be done with the help of head and tail function in R. It is required when we want to understand the data in a vector or perform some calculation for partial data.ExampleConsider the below vectors, we will use head and tail to select ... Read More

Nizamuddin Siddiqui
4K+ Views
Sometimes the lists are contained in another list but we want to access the nested list’s elements. Since these elements are part of a list then cannot be directly accessed, first we need to access the broader list and then the list that contains the element to reach the actual ... Read More

Nizamuddin Siddiqui
3K+ Views
When we deal with large data then the problem of printing the data or output of the analysis arises. Due to this problem, it becomes difficult to have a look at our complete but it can be avoided. Before importing any large data or performing any calculation that may result ... Read More

Nizamuddin Siddiqui
7K+ Views
The aspect ratio of a chart can be changed in ggplot2 and this will be useful if we want a smaller image of the chart. Sometimes, we don’t have large space where the chart will be pasted therefore this functionality becomes useful. Mostly, in research reports we see charts that ... Read More

Nizamuddin Siddiqui
19K+ Views
The warning “removed n rows containing missing values” occurs when we incorrectly specify the range of the values for X-axis or Y-axis. We can this range in ggplot function using scale_x_continuous(limits=c(?, ?)) for x axis and scale_y_continuous(limits=c(?, ?)) for y axis. If the range will be larger than the actual ... Read More

Nizamuddin Siddiqui
2K+ Views
Since visualization is an essential part of data analysis, we should make sure that the plots are created in a form that is easily readable for users. For this purpose, the facets in a bar chart helps us to understand the factor variable levels for another factor. To create such ... Read More

Nizamuddin Siddiqui
285 Views
There are some annoying messages we get while loading a package in R and they are not useful until and unless we are not loading a new package. Since these messages looks like outputs they might be confusing especially when we are analysing string data. Therefore, we must get rid ... Read More