Excel scatterplot graph update automatically

Question

My problem is as follows: The user inputs two numbers between 2 and 25, these numbers are used to create a grid. Every point on the grid has (x,y) coordinates. Based on the amount of points the user chose, my excel sheet is filled up with up to 25x25 (x,y) coordinates.

Example: A 6x7 grid is chosen by the user, the table is filled with 42 (x,y) coordinates and all other values in the table are set to "".

Now I want to use a scatterplot with lines connecting each array to plot the data.

Problem 1: If I only select the 6x7 part of the table that has values in it and create the scatterplot the result is correct. Until the user specifies a different grid, for example 8x9, then the graph is obviously missing two rows and two columns of input data.

Problem 2: If I select the entire 25x25 part of the table, including all the "" values, the graph axes get messed up. The y-axis works properly, but the x-axis shows sequential values (0-7) instead of the x-coordinates.

Problem 3: If I replace all the "" values in the table to 0 or NaN and plot the entire table the axes are correct, but the lines between the scatter data get messed up.

Question: Is there a way to automatically change the input data for the plot, or is there a way to correctly display the values on the x-axis if I select all the data?

Answer 1

Not sure this will work in your case, but it's worth a try, especially since no one's addressed your post in 3+ hours. I've had success with this approach: 1) charting the largest data set, 2) copying the resulting chart, and 3) trimming the data it draws from to produce all smaller data sets.

To get this to work takes a lot of thought in laying out that largest data set so that all the other plots follow as needed. To illustrate, I've somewhat mimicked your data and in the animated gif I show largest data set, plus 2 others produced by copying it. Then I demonstrate how to make the second one, including the rescaling required to make all plots scaled equally. Notice that I've arranged things so that only one set of x-values feeds all the series. If you can do this, it makes working with the Excel's interface much easier.

Answer 2

After wrestling with it all night I came to the following solution: Instead of setting all the empty cells to "" or zero the cells should be be set to #N/A (not available). The graph properly ignores the #N/A cells exactly like I want it to and updates when values are entered into them.