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How to modify data frame using transform() function in R

We provide effective and economically affordable online training courses for R and Python, click here for more details and course registration ! Similar as with() function in R, transform() function provides a way to work on data frame with simplified code inside its block. transform() is mostly used to modify a data frame in a concise and explicit manner. The basic form of usage is transform(df, new_var = operation) Where df is the object data Read more…

By wilsonzhang746, ago

How to transpose data objects in R

We provide effective and economically affordable training courses for R and Python, click here for more details and course registration ! Tabular data objects in R can be easily transposed with t() function. In the following example, we create a matrix of 2 rows and 3 columns, then transpose it, and the rows and columns are interchanged. In the next example, we create a data frame first, then rows and columns are interchanged with t() Read more…

By wilsonzhang746, ago

Using with() to simply your object operations in R

We provide effective and economically affordable training courses for R and Python, click here for more details and course registration ! with() function in R provides an alternative way of carrying out several operations bypassing inputting object name repeatedly. For example, we have a data frame ‘grade’ on hand, and want to calculate the correlation coefficient between Math and Physics variables and show summary statistics of numerical variables, we can write code as follows: If Read more…

By wilsonzhang746, ago

How to use apply() function in R

We provide effective and economically affordable training courses for R and Python, click here for more details and course registration ! apply() function in R programming is used to perform a specified function, either a R base installation function or an user-written function, to the rows or columns of a matrix or data frame. The basic for of the function is : apply(object, axis, fun) Where object is a matrix or data frame, axis denotes Read more…

By wilsonzhang746, ago

Using probability functions in R

We provide effective and economically affordable training courses for R and Python, click here for more details and course registration ! R provides rich availability of using probability functions. Probability functions in R takes the form [dpqr][prob], Where [dpqr] represent which kind of variates the function works on d – probability density p – cumulative probabilty q – quantile value r – random number generation [prob] denotes which probability distribution is taken on. The following Read more…

By wilsonzhang746, ago

Subseting datasets in R

We provide effective and economically affordable training courses for R and Python, click here for more details and course registration ! When a data frame is created in R, usually parts of it will be used later. Subset of the dataset, either by row or by column, or both can be easily created in R. The following example, only data containing columns for ‘Math’, ‘Physics’, and ‘Chemistry’ are selected and assigned to a new object, Read more…

By wilsonzhang746, ago

Merging and combining datasets using merge(), rbind() and cbind() in R

We provide effective and economically affordable training courses for R and Python, click here for more details and course registration ! R provides two functions which make combine different datasets easy and feasible. rbind() is used when two datasets have same column variables and data observations are combined and expanded, whereas cbind() combines two datasets when they have the same number of rows. And merge() is used when two datasets have common column variables. The Read more…

By wilsonzhang746, ago

How to generate random numbers from Normal, Uniform and Poisson distribution in R

We provide effective and economically affordable training courses for R and Python, click here for more details and course registration ! Doing statistics using R is perfect for many data analysts. Dealing with various statistical distributions and generating random numbers from some widely used distributions are mandatory for data science. In this post, we show how to generate random numbers from Normal, Uniform and Poisson distributions in R. Normal variates can be generated by using Read more…

By wilsonzhang746, ago

How to generate a set of sample data using sample() function in R

We provide effective and economically affordable training courses for R and Python, click here for more details and course registration ! sample() function in R selects random samples from a given population. The population can be all elements of a vector, observations of a data frame, etc. For example, in the following code example, 10 elements are randomly selected a population of 100 integers, with replacement possible. The basic form of sample() is sample(object, n, Read more…

By wilsonzhang746, ago

How to select observations of data frames in R

rdatacode.com provides online training course for R and Python, click here for more info ! When a data frame is applied in data analysis in R, very often some specific rows or observations may be selected. The simplest way to select observations is filling row indices in square brackets. Conditional test can be included into row selection. In the following example, Male students over 23 years old are selected. Date variable can be transformed to Read more…

By wilsonzhang746, ago