Dynamic Pie Chart in Flash 5 - Page 9

Adding the Actions (con't)

Step 4.2 : Calculate total and percents

The following code shows how to use a for loop to do calculations on an array. For questions about the syntax, consult the Flash 5 ActionScript Dictionary. In this section, we also correct for possible rounding error and subtract 1 from the first segment because of the pie slice that already exists on the stage (part of 1st segment).

// Calculate total
for (i=0; i < nElements; i++) {
    nTotal += aCount[i];
}
// Calculate percents
for (i=0; i < nElements; i++) {
    aPercent[i] = math.round((aCount[i]/nTotal)*100);
    nTotalPercent += aPercent[i];  // keep for later fix
    if (i < nElements-1) {
        nAllButLast += aPercent[i];	   // keep this for later fix too
	}
}
// if percents don't add to 100 (because of rounding they can be off by 1), fix last percent
if (nTotalPercent != 100) {
    aPercent[nElements-1] = 100 - nAllButLast;
}
// trace is commented out, but I usually leave them in because then I can cut and paste as needed
// trace("aCount=" + aCount + " nTotal=" + nTotal + " aPercent=" + aPercent + " nTotalPercent=" + nTotalPercent + " nAllButLast=" + nAllButLast);
// subtract 1 from first percent because 1 pie slice exists already
aPercent[0] -= 1;