Pie charts: camembert

### 9.1.15 Pie charts: camembert

You can draw pie charts using the same structure as bar graphs.

The camembert command draws pie charts.

- camembert takes one argument:
  M, a matrix, where each row consists of a label followed by one or more values. If the labels are followed by more than one value, then the first row needs to be identifiers.
- camembert(M) draws a pie chart with a sector for each label, whose size is determined by the corresponding value. If the matrix has more than two columns, then there will be a pie chart for each column of values.

Examples.

- Input:
  camembert([["France", 6],["Germany", 12], ["Switzerland", 5]])
  Output:
- Input:
  camembert([[2,"xyz","abc"],["A",2,5],["B",5,6],["C",6,6]])
  Output: