Minimal mdu writing

[veenstrajelmer]

When reading and saving an mdu file, the output file is much larger since all keywords are written to the file. Among modellers, the preference is to only write the non-default keywords to the mdu file (and maybe some extra ones). This enables you to easily see the non-default model settings. However, one could also argue to want a full list of enabled his/mapoutput, even if some of these values are 1 by default. Either way, this is worth a discussion.

There are also some other formatting alignments with the kernel (dia-file) possible that improve readability:

• align all comments with max spacing between = and comment
• keywords start with capital letter?
• headers like [wind] should be lowercase?