Server Side Programming Articles - Page 1519 of 2646

The default color of boxplot area in R using ggplot2 is white but we might want to change that color to something more attracting, for example blue or red. To do this purpose, we can use geom_boxplot function of ggplot2 package with fill argument by passing the color names.Consider the below data frame −Example Live Demoset.seed(1321) v1

There are multiple ways to fill missing values in data analysis and one of the ways is filling them with the previous value in the same column of the data frame. For example, if we have a column x in data frame df and this columns x contains some NA values then we can fill them with the values in the upper row. This can be done with the help of na.locf function of zoo package.Consider the below data frame −Example Live Demoset.seed(477) x

If we have missing values in a data frame then all the values cannot be considered complete cases and we might want to extract only values that are complete. We might want extract the complete cases for a particular column only. Therefore, we can use negation of is.na for the column of the data frame that we want to subset.Consider the below data frame −Example Live Demoset.seed(123) x

Random sampling is an important part of data analysis, mostly we need to create a random sample based on rows instead of columns because rows represent the cases. To create a random sample of some percentage of rows for a particular value of a column from an R data frame we can use sample function with which function.Consider the below data frame −Example Live Demoset.seed(887) grp

A bar plot represents discrete data and the bars in the bar plot are usually of same color but we might want to highlight a particular bar based on the characteristics of the data or the objective of the analysis project. For example, if a particular bar represents highly severe situation or highly unimportant situation then we can change the color that particular bar so that people can easily point out that bar.Consider the below data frame −Example Live Demox

Sometimes the unique identity column of a data frame is not recorded as intended, it contains only numeric values that does not solve the data characteristic purpose. Therefore, we might want to add a string before those numeric values to make the data more sensible for viewers and analysts. This can be easily done with the help of gsub function.Consider the below data frame −Example Live Demoset.seed(111) x1

Simply use, array_merge() to concatenate two arrays in PHP. Let’s say the following are out arrays −$nameArray1 = array('John','David'); $nameArray2 = array('Mike','Sam');Now, set both the above arrays in array_merge() to concatenate them.The syntax is as follows −array_merge($yourFirstArrayName, $yourSecondArrayName);ExampleThe PHP code is as follows  Live Demo OutputThis will produce the following outputArray ( [0] => John [1] => David [2] => Mike [3] => Sam )

To check whether a string has no whitespace, use the preg_match() in PHP.The syntax is as follows preg_match('/\s/',$yourVariableName);ExampleThe PHP code is as follows Live Demo OutputThis will produce the following outputThe name (John Smith) has the space

For this, you can use the strtotime() method.The syntax is as follows −$anyVariableName= strtotime('anyDateValue + X minute');You can put the integer value in place of X.ExampleThe PHP code is as follows Live Demo OutputThis will produce the following output2020-10-30 10:15:20

Let’s say the following is our PHP array $listOfNames = array('John','David','Mike','David','Mike','David');We want the output to display the count of values in the above array like this −Array ( [John] => 1 [David] => 3 [Mike] => 2 )To get the count, use inbuilt function array_count_values().ExampleThe PHP code is as follows Live Demo OutputThis will produce the following outputArray ( [John] => 1 [David] => 3 [Mike] => 2 )