4.97 sddsslopes

• description: sddsslopes makes straight line fits of column data of the input file with respect to a selected column used as the independent variable. The output file contains a one-row data set of slopes and intercepts for each data set of the input file. Errors on the slope and intercept may be calculated as an option.
• examples: The file corrector.sdds contains beam position monitor (BPM) readbacks as a function of corrector setting. The defined columns are CorrectorSetpoint and the series bpm1, bpm2, etc. The BPM response to the corrector setpoints is calculated with sddsslopes:
  sddsslopes corrector.sdds corrector.slopes -independentVariable=CorrectorSetpoint \  
    -columns=’bpm*’  
    

• synopsis:
  sddsslopes [-pipe=[input][,output]] inputFile outputFile  
    -independentVariable=parameterName [-range=lower,upper]  
    [-columns=listOfNames] [-excludeColumns=listOfNames]  
    [-sigma[=generate]] [-residual=file] [-ascii] [-verbose]  
    

• files: inputFile contains the tabular data for fitting. Multiple data sets are processed one at a time. For optional error processing, additional columns of sigma values associated with the data to be fitted must be present. These sigma columns must be named <name>Sigma or Sigma<name>, the former being searched first.

  outputFile contains a one-row data set for each data set in inputFile. The columns defined have names such as nameSlope and nameIntercept, where name is the name of the fitted data. A string column called IndependentVariable is defined containing the name of the independent variable. If only one file is specified, then the input file is overwritten by the output.

• switches:
  • pipe[=input][,output] — The standard SDDS Toolkit pipe option.
  • -independentVariable=parameterName — Name of the independent variable (default is the first valid column).
  • -range=lower,upper — The range of the independent variable over which the fit is calculated. By default, all data points are used.
  • -columns=listOfNames — Columns to be individually paired with the independent variable for straight line fitting.
  • -excludeColumns=listOfNames — Columns to exclude from fitting.
  • -sigma[=generate] — Calculates errors by interpreting column names <name>Sigma or Sigma<name> as sigma of column <name>. If these columns do not exist, the program generates a common sigma from the residual of a first fit and refits with these sigmas. If -sigma=generate is given, sigmas are generated from the residual of a first fit for all columns irrespective of the presence of sigma columns.
  • -residual=file — Specifies an output file into which the residual of the fits are written. The column names in the residual file are the same as they appear in the input file.
  • -ascii — Make output file in ASCII mode (binary is the default).
  • -verbose — Prints some output to stderr.
• see also: sddspfit()
• author: L. Emery, ANL.