Function：
Demonstrate file data in a pie chart.

Input：
Input a tab delimited text file. Data in the first row is the name of each slice, and data in the second row is the proportion of each slice 

Firefox	IE	Chrome	Safari	Opera	Others
45.0	26.8	12.8	8.5	6.2	0.7	

Parameters：

① Type: define a chart type from one of the following options: pie chart with legend, 3D pie chart

② Title: define the chart title

③ Slice label: define the slice name

④ Color: define color of each slice (number of colors should be the same as number of slices and each color should be separated by a comma ”,”)

Output：

A pie chart in PNG, JPEG, PDF, SVG format.