# Histograms and Density Plots in R

A **histogram **is a graphical representation that organizes a group of data points into user-specified ranges and an approximate representation of the distribution of numerical data.

In R language the histogram is built with the use of hist() function.

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

Parameters:

v:-It is a vector containing numeric values used in the histogram.main:-Itindicates the title of the chart.col:-It is used to set the color of the bars.border:-It is used to set the border color of each bar.xlab:-It is used to give a description of the x-axis.xlim:-It is used to specify the range of values on the x-axis.ylim:-It is used to specify the range of values on the y-axis.breaks:-It is used to mention the width of each bar.

Return:It will return the histogram.

**Example:-**

## R

`v <- ` `c` `(5,9,13,2,50,20,59,36,23,2,8,27,72,14)` ` ` `hist` `(v,xlab = ` `"Weight"` `,col = ` `"red"` `,border = ` `"black"` `)` |

**Output:**

A **density plot **is a representation of the distribution of a numeric variable that uses a kernel density estimate to show the probability density function of the variable. In R Language we use the density() function which helps to compute kernel density estimates. And further with its return value, is used to build the final density plot.

Syntax:density(x)

Parameters:

x:the data from which the estimate is to be computed

Returns:It will return the kernel density.

**Example:**

Used dataset link:-Link

## R

`library` `(readxl)` `library` `(ggplot2)` ` ` `Salary_Data <- ` `read_excel` `(` `"Salary_Data.xls"` `)` ` ` `den <- ` `density` `(Salary_Data$YearsExperience)` ` ` `plot` `(den, frame = ` `FALSE` `, col = ` `"blue"` `,main = ` `"Density plot"` `)` |

**Output:**

We can also create a histogram and a density plot in the same frame.

**Example:**

## R

`hist` `(beaver1$temp, ` ` ` `col=` `"green"` `,` ` ` `border=` `"black"` `,` ` ` `prob = ` `TRUE` `,` ` ` `xlab = ` `"temp"` `,` ` ` `main = ` `"GFG"` `)` ` ` `lines` `(` `density` `(beaver1$temp),` ` ` `lwd = 2,` ` ` `col = ` `"chocolate3"` `)` |

**Output:**