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> Steve, > > Thank you for your help on my problems on SFMOD. > > I have a question on a slightly different subject. It is about the way > LINE plots contours. Right now, I am using gdplot2 with DEVICE=vg to > generate objectively analyzed isobars in a VGF file which can be opened > and edited in NMAP. The goal is to have the isobars smooth enough so > that minimum amount of editing is required. I've already set a couple > of things to smooth the isobars. They are: > > 1. GDPFUN = SM5S(PMSL) > 2. CONTUR = 9/1 > 3. LINE = 5/1/1-1/2/1 Kwan, You might have better luck using a higher number of passes in CONTUR rather than subboxes or SM5S()/SM9S(). I typically find something like CONTUR=3/3 provides a nice amount of smoothing without losing the features of the data. Also note you are misisng the "/" character before the "-1" in LINE above. You can also set IJSKIP to subsample your data by every other point such as IJSKIP=1. Steve Chiswell Unidata User Support > > However, the resulting isobars are still not sufficiently smooth. I > could use SM5S more than once and get smoother isobars outside of high > and low pressure centers. However, some smaller closed centers are > filtered away. I could also increase the # of subboxes to e.g. 64/1 > and get smoother isobars. But then they are broken up into smaller > line segments (although they look like continuous lines in NMAP). The > next thing I do is to set the filter in LINE to 1 (max). Compared with > using 0 for the filter, less points are used to produce the line. > However, there are still too many points used even at 1. I think I'll > need only about half of these points. So I want to double the amount > of point filtering. But I can't set it to 2, right? If I really want > to do that, I'll have to change the filter program itself, right? > > Kwan > > Ticket Details =================== Ticket ID: MGA-118138 Department: Support GEMPAK Priority: Normal Status: Closed