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Guest Observer Facilities & Science Centers Select One AGILE ASCA Astro-H BeppoSAX COBE CGRO Chandra EUVE Fermi (formerly GLAST) GALEX GEMS HETE-2 INTEGRAL ROSAT RXTE Suzaku Swift WMAP XMM-Newton NASA Archives Select One ADS AstroGravS EOSDIS HORIZONS IRSA Keck Archive LAMBDA MAST NExScI (formerly Michelson) NED NSSDC NStED PDS SDAC SPDF Spitzer Science Center HEASARC Tip: View all tips Next: UPper Up: PLT Command Summary Previous: Time Uncertain Uncertain [# [# [#]]] Vary the specified parameter(s) in order to estimate their uncertainties. Each specified parameter, in turn, is stepped and c2 is minimized. Stepping stops when the requested value of Dc2 is obtained. Uncertain can take up to 3 numbers as arguments. If one number contains a decimal point, then that number is interpreted as the requested value of Dc2 (which for the first time defaults to 2.7 and for later times defaults to the previous value). The remaining two numbers in the Uncertain command specify the lower and upper parameter numbers for which you want to estimate the error. If only one number is given (without a decimal point), then the error is generated only for a single parameter. If errors are currently turned off (or do not exist), then the routine works out a correction factor that converts the W-VAR to c2. Web Page Maintained by: Dr. Lawrence E. Brown elwin@redshift.gsfc.nasa.gov