R - Histograms




R - Histograms

A histogram represents the frequencies of values of a variable bucketed into ranges. Histogram is similar to bar chat but the difference is it groups the values into continuous ranges. Each bar in histogram represents the height of the number of values present in that range.

R creates histogram using hist() function. This function takes a vector as an input and uses some more parameters to plot histograms.

Syntax

The basic syntax for creating a histogram using R is −

hist(v,main,xlab,xlim,ylim,breaks,col,border)

Following is the description of the parameters used −

  • v is a vector containing numeric values used in histogram.

  • main indicates title of the chart.

  • col is used to set color of the bars.

  • border is used to set border color of each bar.

  • xlab is used to give description of x-axis.

  • xlim is used to specify the range of values on the x-axis.

  • ylim is used to specify the range of values on the y-axis.

  • breaks is used to mention the width of each bar.

Example

A simple histogram is created using input vector, label, col and border parameters.

The script given below will create and save the histogram in the current R working directory.

 Live Demo

# Create data for the graph.
v <-  c(9,13,21,8,36,22,12,41,31,33,19)

# Give the chart file a name.
png(file = "histogram.png")

# Create the histogram.
hist(v,xlab = "Weight",col = "yellow",border = "blue")

# Save the file.
dev.off()

When we execute the above code, it produces the following result −

R - Histograms

Range of X and Y values

To specify the range of values allowed in X axis and Y axis, we can use the xlim and ylim parameters.

The width of each of the bar can be decided by using breaks.

 Live Demo

# Create data for the graph.
v <- c(9,13,21,8,36,22,12,41,31,33,19)

# Give the chart file a name.
png(file = "histogram_lim_breaks.png")

# Create the histogram.
hist(v,xlab = "Weight",col = "green",border = "red", xlim = c(0,40), ylim = c(0,5),
   breaks = 5)

# Save the file.
dev.off()

When we execute the above code, it produces the following result −

R - Histograms



Frequently Asked Questions

+
Ans: R - Boxplots view more..
+
Ans: R - Bar Charts view more..
+
Ans: R - Pie Charts view more..
+
Ans: R - Histograms view more..
+
Ans: R - Line Graphs view more..
+
Ans: R - Scatterplots view more..
+
Ans: R - Mean, Median and Mode view more..
+
Ans: R - Linear Regression view more..
+
Ans: R - Multiple Regression view more..
+
Ans: R - Logistic Regression view more..
+
Ans: R - Normal Distribution view more..
+
Ans: R - Binomial Distribution view more..
+
Ans: R - Poisson Regression view more..
+
Ans: R - Analysis of Covariance view more..
+
Ans: R - Time Series Analysis view more..
+
Ans: R - Nonlinear Least Square view more..
+
Ans: R - Decision Tree view more..
+
Ans: R - Random Forest view more..




Rating - NAN/5
544 views

Advertisements