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Nizamuddin Siddiqui has Published 2307 Articles

Nizamuddin Siddiqui
582 Views
Aesthetics is one of the most important aspect of a chart, hence we should try to use the best possible aesthetic properties in a plot. In a bar chart, we can represent the center of bars in many ways and one such way is using dots at the center of ... Read More

Nizamuddin Siddiqui
377 Views
Generally, cumulative sums are calculated for a single variable and in some cases based on a single categorical variable, there are very few situations when we want to do it for two categorical variables. If we want to find it for two categorical variables then we need to convert the ... Read More

Nizamuddin Siddiqui
870 Views
To create a vector with lowercase we can use the word letters and for uppercase the word LETTERS is used in R. If we want to create a vector with both type of letters then both of these words can be combined using c function and if want to create ... Read More

Nizamuddin Siddiqui
3K+ Views
The random sample can be repeated by using replicate function in R. For example, if we have a vector that contains 1, 2, 3, 4, 5 and we want to repeat this random sample five times then replicate(5, x) can be used and the output will be matrix of the ... Read More

Nizamuddin Siddiqui
302 Views
To find the minimum value of a numeric vector we can directly use min function but if the values are read with double-inverted commas then min function does not work. In this case, we will have to use as.numeric with the vector name so that it can be converted to ... Read More

Nizamuddin Siddiqui
520 Views
After getting some experience with data frame people generally move on to data.table object because it is easy to play with a data.table object as compared to a data frame. We also need to create a subset of a data.table object and it can be easily done with the help ... Read More

Nizamuddin Siddiqui
3K+ Views
To combine two factor vectors, we can extract the unique levels of both the vectors then combine those levels. This can be done by using unique function. Also, we can set the levels of the original vectors to the combination of the levels, in this way, we can complete both ... Read More

Nizamuddin Siddiqui
332 Views
We can use %in% to check whether a matrix element is present in another matrix or not. For example, suppose we have two matrices defined as − M1 1 2 3 1 2 3 1 2 3 M2 1 2 3 4 5 6 7 8 9Then M1%in%M2 will ... Read More

Nizamuddin Siddiqui
325 Views
The xtable function of xtable package creates a Latex table. We can use digits argument with negative sign to convert the values in the original table into scientific form. For example, if we have a data frame defined as df then we can read it with xtable as xtable(df, digits=-10).Loading ... Read More

Nizamuddin Siddiqui
729 Views
To convert a list into an array then firstly we need to unlist the list elements and then use the array function. For example, if we have a list defined as List then it can be converted into an array using the command array(unlist(List)). Suppose the list contain the elements ... Read More