Negative Sigma in Gaussian Fit on Linux/egcs1.1.1

From: Wolfgang Korsch (wkorsch@server1.pa.uky.edu)
Date: Mon Mar 15 1999 - 16:45:09 MET 

  Dear ROOT team,
  
   I tried to do gaussian fit and got the following result on LINUX RH 5.2
   w/ EGCS1.1.1:
   
   FCN=3.47372 FROM MIGRAD    STATUS=CONVERGED     114 CALLS         115 TOTAL
                     EDM=7.11533e-06    STRATEGY= 1      ERROR MATRIX ACCURATE 
  EXT PARAMETER                                   STEP         FIRST   
  NO.   NAME      VALUE            ERROR          SIZE      DERIVATIVE 
   1  Constant     4.57000e+01   4.66737e+00   4.66669e-03  -1.96269e-04
   2  Mean         1.20224e+07   4.70724e+01   5.73270e+00   2.06634e-06
   3  Sigma       -4.72385e+02   1.23139e+01   1.40189e-02   3.17310e-04


   The data is fine and even the fit looks fine when plotted on top of the
   data. Running the same software on DU 4.0 gives the same Sigma with
   a positive sign!!
   
   I use ROOT version 2.21/07
   
   Any ideas? Thanks.
   
     Wolfgang

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