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On 6/2/2010 7:46 AM, Jon Blower wrote: >> John Caron wrote: >> 1. what does ncWms currently do for default? Use data min/max? > > No - ncWMS uses a separate config file, which the sysadmin edits > manually or through a web GUI. This allows configuration > per-variable. > > I think this is a separate issue from data min/max - this is a > *suggested* scale, which doesn't need to be precise. On 6/2/2010 3:03 PM, Jon Blower wrote: >> John Caron wrote: >> what does the system do if the admin doesnt set a value >> for that dataset? > > ncWMS scans each dataset when it's first loaded into the system > and makes a test extraction of a chunk of data from the first > timestep and first z level from each variable. Then it finds > the min and max of this data subset, adding 10% at top and > bottom. It's far from perfect but it at least gives a reasonable > guess, which the sysadmin can override if it turns out to be a > bad choice. > > If that doesn't work for any reason, ncWMS applies the default > range [-50:50]. But this doesn't happen very often. > > The estimated scale ranges are persisted to the ncWMS config > file so they don't have to be recalculated when the server is > rebooted. > > I guess this approach would be difficult to apply in TDS, where > the data catalogs could be very big. > > Jon Ticket Details =================== Ticket ID: XIG-399067 Department: Support THREDDS Priority: Urgent Status: Open