Creating a stacked Google Chart? - google-visualization

Question

I am trying to create a stacked Google Chart. It's easy, but with the current data set I have i'm a bit confused. I need a stacked chart, but with some of the bars I don't need all columns. Some, I only need 2, 3 or sometimes just 1 column of data. For example, suppose I have:
data.addColumn('string', 'Topping');
data.addColumn('number', 'Nescafe Instant');
data.addColumn('number', 'Folgers Instant');
data.addColumn('number', 'Nescafe Beans');
data.addColumn('number', 'Folgers Beans');
data.addRows([
['2001', 321, 621, 816, 319],
['2002', 163, 231, 539, 594],
['2003', 125, 819, 123, 578],
['2004', 197, 536, 613, 298]
]);
I need this:
data.addColumn('string', 'Topping');
data.addColumn('number', 'Nescafe Instant');
data.addColumn('number', 'Folgers Instant');
data.addColumn('number', 'Nescafe Beans');
data.addColumn('number', 'Folgers Beans');
data.addRows([
['2001', 321, 621, 816, 319],
['2002', 163, 231, 539, 594],
['2003', 578],
['2004', 197, 536]
]);
With this current format, it does not work. Not only that, the third row (578) should refer to Folgers Beans and not Nescafe Instant. How can I fix these problems so that the graph displays and it also displays with the correct information?

Answer 1

I have figured out the answer. In order to solve this problem, you have to add undefined to the empty fields. For example:
data.addColumn('string', 'Topping');
data.addColumn('number', 'Nescafe Instant');
data.addColumn('number', 'Folgers Instant');
data.addColumn('number', 'Nescafe Beans');
data.addColumn('number', 'Folgers Beans');
data.addRows([
['2001', 321, 621, 816, 319],
['2002', 163, 231, 539, 594],
['2003', undefined, undefined, undefined, 578],
['2004', undefined, undefined, 197, 536]
]);