Found 33676 Articles for Programming

How to find the n number of largest values in an R vector?

Nizamuddin Siddiqui
Updated on 04-Sep-2020 10:48:34

271 Views

A vector may have thousands of values and each of them could be different or same also. It is also possible that values can be grouped or randomly selected but having few similar values. Irrespective of the values in a vector, to find some largest values we need to sort the vector in ascending order then the largest values will be selected.Examples> x1 x1 [1] -1.4447473195 3.2906645299 -0.4680055849 0.1611487482 -0.7715094280 [6] 0.4442103640 0.3702444686 0.0783124252 1.3476432299 1.0140576107 [11] -0.0968917066 0.4628821017 0.3102594626 -0.2946001275 0.1498108166 [16] -0.6002154305 0.5905382364 1.3892651534 0.1008921325 -0.6486318692 [21] -0.0562831933 -0.6887431711 0.4907512082 -0.3994662410 0.7827897030 [26] 0.5294704584 -1.3802965730 -0.6159076490 -0.0009408529 1.6182294859 ... Read More

How to cut the elements of a numeric vector into multiple intervals in R?

Nizamuddin Siddiqui
Updated on 04-Sep-2020 10:45:49

479 Views

A numeric vector may contain a large number of elements; therefore, we might want to convert that vector into a vector of intervals. For example, if we have 1 to 10 values in a vector then we might want to convert that vector into a vector of intervals such as (1, 5) for 1, 2, 3, 4, and 5 and (6, 10) for 6, 7, 8, 9, 10). This can be done by using cut function where we will use breaks argument to combine the vector elements in an interval.Examples Live Demo> x1 x1Output[1] 1 2 3 4 5 6 7 ... Read More

How to find the cumulative sums if a vector contains NA values in R?

Nizamuddin Siddiqui
Updated on 04-Sep-2020 10:31:35

847 Views

The cumulative sums are the sum of consecutive values and we can take this sum for any numerical vector or a column of an R data frame. But if there exits an NA, then we need to skip it and therefore the size of the cumulative sums will be reduced by the number of NA values. If we have NA values in a vector then we can ignore them while calculating the cumulative sums with cumsum function by using !is.na.Examples Live Demo> x1 x1Output[1] 1 2 3 4 5 6 7 8 9 10 NA > cumsum(x1[!is.na(x1)]) [1] 1 3 6 ... Read More

How to convert a decimal value or a vector of decimal values to fractional form in R?

Nizamuddin Siddiqui
Updated on 04-Sep-2020 09:32:04

4K+ Views

A fraction form of a decimal value is the form of the value represented with division sign. For example, representing 0.5 as 1 / 2. In R, we can use fractions function of MASS package to convert a decimal value or a vector of decimal values to fractional form. To do so, we just need to pass the value in fractions function as fractions(“Decimal_value or Vector_Of_Decimal_Values”).Loading MASS package −Examples> library(MASS)Output> fractions(0.14) [1] 7/50 > fractions(1.14) [1] 57/50 > library(MASS) > fractions(0.5) [1] 1/2 > fractions(0.3) [1] 3/10 > fractions(0.31) [1] 31/100 > fractions(1.31) [1] 131/100 > fractions(2.01) [1] 201/100 > ... Read More

How to change the angle of annotated text in plot created by using ggplot2 in R?

Nizamuddin Siddiqui
Updated on 04-Sep-2020 09:30:28

276 Views

To annotate the text inside a plot created by ggplot2, we can use annotate function. It is used to give some explanation about the plot or add any useful information that will help readers to understand the plot in a better way. Sometimes, we might want to change the angle of the annotated text, especially in cases where we have some information that is presented vertically in the plot, therefore, we can use angle argument of the annotate function.ExampleConsider the below data frame − Live Demo> x y df dfOutput      x       y 1 4.086537 5.890591 2 ... Read More

How to create a dot plot using ggplot2 in R?

Nizamuddin Siddiqui
Updated on 04-Sep-2020 09:28:00

501 Views

A dot plot is a type of histogram that display dots instead of bars and it is created for small data sets. In ggplot2, we have geom_dotplot function to create the dot plot but we have to pass the correct binwidth which is an argument of the geom_dotplot, so that we don’t get the warning saying “Warning: Ignoring unknown parameters: bins `stat_bindot()` using `bins = 30`. Pick better value with `binwidth`.”ExampleConsider the below data frame −> x df1 library(ggplot2)Creating the dot plot of x −> ggplot(df1, aes(x))+geom_dotplot(binwidth=0.2)OutputLet’s have a look at one more example −> y df2 ggplot(df2, aes(y))+geom_dotplot(binwidth=0.2)OutputRead More

How to determine the percentiles of a vector values in R?

Nizamuddin Siddiqui
Updated on 04-Sep-2020 09:26:13

261 Views

Percentile helps us to determine the values that lie at a certain percent in a data set. For example, if we have a vector of size 100 with containing any values and suppose that the tenth-percentile of the vector is 25, which means there are ten percent values in the vector that are less than 25, or we can say, there are ninety percent values in the vector that are greater than 25. We can find percentiles of a vector values using quantile function in R.Examples Live Demo> x1 x1Output[1] 7 1 7 6 6 5 3 1 5 5 4 ... Read More

How to delete different rows and columns of a matrix using a single line code in R?

Nizamuddin Siddiqui
Updated on 04-Sep-2020 09:24:37

1K+ Views

Deletion or addition of rows and columns in a matrix of any size is mostly done by using single square brackets and it is also the easiest way. To delete rows and columns, we just need to use the column index or row index and if we want to delete more than one of them then we can separate them by commas by inserting them inside c as c(-1, -2). If we want to delete more than one rows or columns in a sequence then a colon can be used.Examples Live Demo> M MOutput   [, 1] [, 2] [, 3] [, ... Read More

How to extract p-values for intercept and independent variables of a general linear model in R?

Nizamuddin Siddiqui
Updated on 04-Sep-2020 09:19:37

460 Views

General linear model does not assume that the variables under consideration are normally distributed, therefore, we can use other probability distributions to create a general linear model. We should actually say that if the data does not follow normal distribution then we can try different distributions using general linear model and check whether the model is appropriate or not. The p-values plays an important role in selecting the best model and we might want to extract them from the model object. This can be done by using coef function.ExampleConsider the below data frame − Live Demo> set.seed(123) > var1 var2 var3 ... Read More

How to check whether the elements of a vector are arranged in an increasing order or decreasing order?

Nizamuddin Siddiqui
Updated on 04-Sep-2020 11:53:03

944 Views

A vector can contain values that are increasing or decreasing in nature or they can be also random which means a higher value may come after a lower one which is followed by a higher value. An example of increasing arrangement of elements of vector is 1, 2, 3 and the opposite of that would be decreasing arrangement. We can check whether a vector is arranged in increasing order or decreasing order by checking whether the difference between all values of the vector is greater than or equal to zero or not and it can be done by using diff ... Read More

Advertisements