support for absolute parameters and absparmax(N)

[hansonmcoombs]

From what I can see there is no explict support for setting parameter PARCHGLIM to 'absolute(N)'.

You can manually set the PARCHGLIM field in the parameter data as follows:

pst.parameter_data.loc[idx1, 'parchglim'] = 'absolute(1)'
pst.parameter_data.loc[idx2, 'parchglim'] = 'absolute(2)'

But it does not look like there is a way to set the absparmax(N) values in the control data or write them on line 6 of the pest control file. (e.g. absparmax(1)=0.1 absparmax(2)=0.2)

If I am mistaken, please correct me and maybe add a note somewhere in the documentation.

If I am not mistaken I would suggest implementing:

1. an absparmax variable in control data with a default value of an implmented as an empty list [] in the dataframe (N by index +1 ) e.g. [N=1, N=2]
2. alternativley it could be implmented as an empty dictionary and should users need to pass absolute paramter limits they simply call control_data.absparmax[1]=0.1, but this would break the pd.Dataframe object structure
3. a sanity check that if absparmax is not empty or 'absolute' is in the parameter data, check that the right number of absparmax exist
4. a modification to the control data.write and write_keyword methods so that the appropriate formatting is written to line 6 of the pst control file (assuming len(control_data.absparmax)!=0)

I'm happy to take a stab at implementing this, but I thought I would check that you all don't have some plan in the works already or that I missed something.

I'm not super familar with the pest control file version 2 style, so a reference to that would help me not mess up :)

[jtwhite79]

I'm happy for you to have a go at this! Let us know if you get stuck and we can try to help (i don't use these options so might not be very helpful....)

[hansonmcoombs]

Sounds good I'll put it on my todo list... it may be a min