How to deal with error 'height' must be a vector or a matrix while creating barplot?

The error 'height' must be a vector or a matrix while creating barplot occurs when we provide data frame name instead of column names or read it with as.matrix. If we want to create bar plot for columns in a data frame then the data frame needs to be read as matrix.

For Example, if we have a data frame called df then we can create the barplot of columns in df by using the command given below −

barplot(as.matrix(df))

Example

Following snippet creates a sample data frame −

df<-data.frame(x=rpois(20,2),y=rpois(20,5)) df

The following dataframe is created

 x y 1 2 10 2 2 3 3 1 6 4 2 6 5 4 4 6 2 5 7 3 4 8 2 4 9 2 9 10 3 5 11 3 4 12 2 2 13 1 4 14 2 6 15 1 8 16 2 2 17 4 1 18 1 5 19 4 4 20 2 9

To create the bar plot with data frame name on the above created data frame, add the following code to the above snippet −

df<-data.frame(x=rpois(20,2),y=rpois(20,5)) barplot(df) Error in barplot.default(df) : 'height' must be a vector or a matrix

The correct way to create the bar plot is as follows −

df<-data.frame(x=rpois(20,2),y=rpois(20,5)) barplot(as.matrix(df))

Output

If you execute all the above given snippets as a single program, it generates the following Output −