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Nizamuddin Siddiqui has Published 2307 Articles

Nizamuddin Siddiqui
168 Views
To find the row variance of columns having same name in data.table object in R, we can follow the below steps −First of all, create a data.table object with some columns having same name.Then, use tapply along with colnames and var function to find the row variance of columns having ... Read More

Nizamuddin Siddiqui
306 Views
To find the row mean of columns having same name in R data.table, we can follow the below steps −First of all, create a data.table with some columns having same name.Then, use tapply along with colnames and mean function to find the row mean of columns having same name.ExampleCreate the ... Read More

Nizamuddin Siddiqui
105 Views
To find the row standard deviation of columns having same name in R matrix, we can follow the below steps −First of all, create a matrix with some columns having same name.Then, use tapply along with colnames and sd function to find the row standard deviation of columns having same ... Read More

Nizamuddin Siddiqui
537 Views
To find the row mean of columns having same name in R matrix, we can follow the below steps −First of all, create a matrix with some columns having same name.Then, use tapply along with colnames and mean function to find the row mean of columns having same name.ExampleCreate the ... Read More

Nizamuddin Siddiqui
1K+ Views
To find the row mean of columns having same name in R data frame, we can follow the below steps −First of all, create a data frame with some columns having same name.Then, use tapply along with colnames and mean function to find the row mean of columns having same ... Read More

Nizamuddin Siddiqui
272 Views
To find the sin of each value in columns if some columns are categorical in R data frame, we can follow the below steps −First of all, create a data frame.Then, use numcolwise function from plyr package to find the sin of each value in columns if some columns are ... Read More

Nizamuddin Siddiqui
295 Views
To convert values in alternate rows to negative R matrix, we can follow the below steps −First of all, create a matrix.Then, use vector multiplication with 1 and minus 1 to convert values in alternate rows to negative.ExampleCreate the matrixLet’s create a matrix as shown below −M

Nizamuddin Siddiqui
204 Views
To convert values in alternate rows to negative in data.table object in R, we can follow the below steps −First of all, create a data.table object.Then, use vector multiplication with 1 and minus 1 to convert values in alternate rows to negative.ExampleCreate the data.table objectLet’s create a data.table object as ... Read More

Nizamuddin Siddiqui
961 Views
To remove hyphen at last position from every value in R data frame column, we can follow the below steps −First of all, create a data frame with a column having hyphen at last position in every value.Then, use gsub function to remove hyphen at last position from every value ... Read More

Nizamuddin Siddiqui
1K+ Views
To find the number of zeros in each column of a matrix in R, we can follow the below steps −First of all, create a matrix.Then, use colSums function to find the number of zeros in each column.Example 1Create the matrixLet’s create a matrix as shown below −M1Read More