xy charts??

**Telegraph Sam** · 04-01-2010, 03:45 PM

Trying to figure out how to graph / chart a relationship between one dependent and two independent variables. The tutorials I have found all address the opposite. I suspect the answer will be contained in xy scatter charts. But do I use two / dual axes as I once did with line charts?? If so I can't work out how to do this, how to set out the data and where to find the dual axes option button.

Tks for assistance!

**shg** · 04-01-2010, 04:05 PM

That would be a surface chart, and Excel has very limited capabilities for them.

**Telegraph Sam** · 04-01-2010, 04:18 PM

I can visualize a simple surface (= 2 dimensional?) chart with independent variables on the x and y axes respectively and the dependent values graphed against each. As I said I've a feeling that x y charts do this, with or without dual axes, but I can't quite figure out how to do it. Trial and error?

**shg** · 04-01-2010, 04:45 PM

I have a feeling that no x-y charts do this. You need need three independent axes.

**Telegraph Sam** · 04-01-2010, 05:10 PM

If you wanted to chart (for example) the second hand values of a model of a car against the age and the mileage as displayed in various used car adverts, I can't see why Excel cannot do this (without resorting to 3 axes - I can't think in 3 dimensions!). There are only two independent variables to go on 2 independent axes. I thought this was what x y charts were designed to do.

**shg** · 04-01-2010, 07:01 PM

Maybe. Draw one by hand, scan it and post it.

**teylyn** · 04-02-2010, 09:36 PM

Telegrap Sam, please stop quoting whole posts. It's just clutter. Use the quick reply box or the New Reply button, not the Quote button when replying to a post.

thanks

**Andy Pope** · 04-03-2010, 05:57 AM

The simple solution, using your matrix, is to plot a line chart.

The two variations are included in the attached.

**Telegraph Sam** · 04-03-2010, 05:16 PM

Andy. Your two latest tks are no doubt neater solutions but unfortunately don't demonstrate the dependency on the combination of "age" and "mileage" which is what I had in mind when I thought of xy scatter graphs. Further thought and experimentation with what you sent, over Easter ...