A histogram contains rectangular area to display the statistical information which is proportional to the frequency of a variable and its width in successive numerical intervals. A graphical representation that manages a group of data points into different specified ranges. It has a special feature which shows no gaps between the bars and similar to a vertical bar graph.
R creates histogram using hist() function.
Syntax:
hist(v, main, xlab, xlim, ylim, breaks, col, border)Parameters:
- v: This parameter contains numerical values used in histogram.
- main: This parameter main is the title of the chart.
- col: This parameter is used to set color of the bars.
- xlab: This parameter is the label for horizontal axis.
- border: This parameter is used to set border color of each bar.
- xlim: This parameter is used for plotting values of x-axis.
- ylim: This parameter is used for plotting values of y-axis.
- breaks: This parameter is used as width of each bar.
Creating a simple Histogram
Approach: In order to create Histogram chart:
- Creating a simple histogram chart by using the above parameter.
- This vector v is plot using hist().
Example:
# Create data for the graph. v < - c( 19 , 23 , 11 , 5 , 16 , 21 , 32 , 14 , 19 , 27 , 39 ) # Create the histogram. hist(v, xlab = "No.of Articles " , col = "green" , border = "black" ) |
Output:
Range of X and Y values
Approach: To describe the range of values we need to do following steps:
- We can use the xlim and ylim parameter in X-axis and Y-axis.
- Take all parameters which are required to make histogram chart.
Example
# Create data for the graph. v < - c( 19 , 23 , 11 , 5 , 16 , 21 , 32 , 14 , 19 , 27 , 39 ) # Create the histogram. hist(v, xlab = "No.of Articles" , col = "green" , border = "black" , xlim = c( 0 , 50 ), ylim = c( 0 , 5 ), breaks = 5 ) |
Output:
Using histogram return values for labels using text()
Approach: To create histogram return value chart:
# Creating data for the graph. v < - c( 19 , 23 , 11 , 5 , 16 , 21 , 32 , 14 , 19 , 27 , 39 , 120 , 40 , 70 , 90 ) # Creating the histogram. m< - hist(v, xlab = "Weight" , ylab = "Frequency" , col = "darkmagenta" , border = "pink" , breaks = 5 ) # Setting labels text(m$mids, m$counts, labels = m$counts, adj = c( 0.5 , - 0.5 )) |
Output: When we execute the above code, it shows the following result-
Histogram using non-uniform width
Approach: creating different width histogram chart:
- By using above parameters, we created histogram using non-uniform width.
Example
# Creating data for the graph. v < - c( 19 , 23 , 11 , 5 , 16 , 21 , 32 , 14 , 19 , 27 , 39 , 120 , 40 , 70 , 90 ) # Creating the histogram. hist(v, xlab = "Weight" , ylab = "Frequency" , xlim = c( 50 , 100 ), col = "darkmagenta" , border = "pink" , breaks = c( 5 , 55 , 60 , 70 , 75 , 80 , 100 , 140 )) |
Output: