GAMS - writing output to excel file using GDX - gams-math

Question

I am in the midst of exporting data from GAMS to excel. As such, I am using the GDX utilities.
Say that I have two variables, x and y, defined over the set i. The set i={1,2,3,4}. As such, x(i) and y(i) have four data points each.
I first unload the output to a GDX file:
execute_unload "output_ex.gdx"
x
y
;
Thereafter, I write the variable levels to Excel file. Currently, I write it as
execute 'gdxxrw.exe Output.gdx par=XXX rng=XXX !a1'
execute 'gdxxrw.exe output_ex.gdx par=x rng=x!a1'
execute 'gdxxrw.exe output_ex.gdx par=y rng=y!a1'
This creates an excel file, with 2 sheets, x and y, each containing the 4 values of x and y, starting in cell a1, with the set indices (i=1..4) in the first column. I would like to have instead, a single sheet. This can be achieved, by say
execute 'gdxxrw.exe Output.gdx par=XXX rng=XXX !a1'
execute 'gdxxrw.exe output_ex.gdx par=x rng=x!a1'
execute 'gdxxrw.exe output_ex.gdx par=y rng=x!a3'
Here, I obtain x and y in a single sheet, entitled x. However, the issue is that the indices repeat, i.e. the index is created in duplicate on cell a3, so I have a separate row of the same indices for x and y. Is there any way of having the index only in the first row, and the subsequent rows containing just the data, identified by variable names? This would make it aesthetically more pleasing and easier to manipulate.
Many thanks!

Answer 1

You could combine the two parameters in one in GAMS already before exporting it, like this:
Set i / i1*i4 /
header / x,y /;
Parameter
x(i)
y(i)
xy(i, header);
* Fill with random data
x(i) = uniformInt(2,6);
y(i) = uniformInt(4,7);
* Combine in one parameter
xy(i,'x') = x(i);
xy(i,'y') = y(i);
execute_unload "output_ex.gdx" xy;
execute 'gdxxrw.exe output_ex.gdx par=xy rng=xy!a1'