GAMS compile to GDX drops column with all zero values

Question

NOTE: Update (but not solved) Below

In my use case for GAMS I wish to define a collection of static variables in a .gdx file rather than in the main model.gms script. This is not an issue unless I define a column that contains only zero (0) values. When defining a table ("data") like this and choosing "Run with GDX Creation in GAMS studio. I get a .gdx file with a missing column.

Set indexA  /ch1*ch5/;

Table data(indexA, *) 

        A_min    A_max   B_min    B_max    
ch1     1        10      0        7
ch2     2        10      0        6
ch3     3        10      0        5
ch4     4        10      0        4
ch5     5        10      0        3;

Copy and pasted .gdx contents:

IndexA *        Value
ch1    A_min    1
ch1    A_max    10
ch1    B_max    7
ch2    A_min    2
ch2    A_max    10
ch2    B_max    6
ch3    A_min    3
ch3    A_max    10
ch3    B_max    5
ch4    A_min    4
ch4    A_max    10
ch4    B_max    4
ch5    A_min    5
ch5    A_max    10
ch5    B_max    3

Column 'B_min' is nowhere to be seen. When trying to load this .gdx back into my script it gives me an error where I try to access 'B_min' and says "Label is unknown". If I change the value to be non zero, it is not a problem, but I need it to be zero! I have tried using 0.0 vs 0. No change. Why can't I define something to be zero and have it save in my .gdx?

Edit / Update: I created an ugly work around for this. I set all of my "B_min values to -1 in gams, created my .gdx file with the column, but the wrong values. Loaded the .gdx file into python using the GAMS API, iterated over each entry in 'data' to change the -1 values to 0 and saved it. This new .gdx file now works in my test model. I would still really like to get this zero thing solved for others on my team who are not going to use this work around with the python API.

Answer 1

For efficiency GAMS does not store default values, thus no zeros in parameters. What you probably can do is setting $onEps. This will transform your zeros into eps, which is numerically still zero but makes it into the GDX file.