draw a pie chart
angles=epie([value[,valueText[,legendText[,dash[,offset[,color]]]]]])
value :
value of pie slide
valueText :
text of value , if empty string then no text at pie slice
legendText :
text of legend, if empty string then no legend
dash :
border type,0=solid line,>0=dash length,
<0=fill slice with color
offset :
radial offset of pieslice, default=0
color :
color of pie, vector [r g b]
angles :
n x 2 matrix of pie slice angles, if epie without parameter
[pieSlice1StartAngle pieSlice1SizeAngle;
pieSlice2StartAngle ...