Session Logs¶

Session logs are a way for users to keep track of work they have done. They record the execution of an ISIS program or sequence of ISIS programs. Info written to the log includes:

Program run, with:
- Version, Date/time run, Computer name, Username, Description
- Groups for:
  - User input parameters, Results, Accounting, and Errors (if any occur)

Format¶

Session logs are output in the Parameter Value Language (PVL) format; below are two examples.

Session Log File recording a High Pass Filter

Object = Highpass
  IsisVersion        = 3.0
  ProgramVersionDate = 2003-05-16
  ExecutionDateTime  = 2003-06-25T12:18:45
  ComputerName       = char
  UserName           = janderso
  ProgramDescription = "Apply a high pass filter to a cube"

  Group = UserParameters
    From      = input.cub
    To        = output.cub
    Samples   = 5
    Lines     = 5
    Low       = "Use all pixels" 
    High      = "Use all pixels"
    Minimum   = 0
    Propagate = True
  EndGroup

  Group = Results
    PixelsChanged  = 1024000
    PercentChanged = 100.0
  EndGroup

  Group = Accounting
    ConnectTime  = 0:00:05.2
    CpuTime      = 0:00:04.1
    DirectIO     = 0
    PageFaults   = 2673
    ProcessSwaps = 0
  EndGroup
EndObject

Session Log File with Error

Notice Group = Error and the associated error information.

Object = Highpass
  IsisVersion        = 3.0
  ProgramVersionDate = 2003-05-16
  ExecutionDateTime  = 2003-06-25T12:18:45
  ComputerName       = char
  UserName           = janderso
  ProgramDescription = "Apply a high pass filter to a cube"

  Group = UserParameters
    From      = moon.cub
    To        = output.cub
    Samples   = 5
    Lines     = 5
    Low       = "Use all pixels" 
    High      = "Use all pixels"
    Minimum   = 0
    Propagate = True
  EndGroup

  Group = Error
    Program = Highpass
    Class   = "I/O ERROR"
    Code    = -3
    Message = "Unable to open cube [moon.cub]"
    Source  = IsisCube.cpp
    Line    = 203
  EndGroup
EndObject

Output¶

Output of session logs can be set with ISIS user preferences. File and Terminal/STDOUT output can both be set On or Off independently. If FileOutput is On, then the FileName and FileAccess parameters will apply.

    # Isis Preferences File
    Group = SessionLog
      TerminalOutput = On | Off
      FileOutput = On | Off
      FileName = print.prt
      FileAccess = Append | Overwrite
    EndGroup

Terminal Output and Redirection

If TerminalOutput is On, info will be logged to STDOUT (the terminal), and standard Unix constructs may be used to redirect the output. For example,

stats from=moon.cub > stats.log