1 VALD Version 3.0 PRESELECT Version 3.3
   2 
   3 1. Functionality
   4 
   5 This program fulfills three functions: it (1) reads control
   6 parameters via standard input, (2) opens and reads and merges
   7 database file(s) and (3) filters the data and outputs it via
   8 standard output.
   9 
  10 PRESELECT3 usage can be found out using special call:
  11 preselect3 -help
  12 
  13 1.1. Standard input
  14 
  15 Any text
  16 Standard input consists of several lines. Any text in any line
  17 following #-symbol is ignored and thus can be used as a comment.
  18 The input has the following layout:
  19 
  20 <starting_wavelength>,<ending_wavelength> # wavelength range
  21 <maximum_number_of_selected_lines> # 0 = no restriction
  22 <Ion or element or empty line>     # E.g. Fe 1 - neutral iron
  23                                    #      Fe   - all iron ions
  24                                    #           - all elements
  25 <configuration_file>               # VALD3 configuration file
  26 0                                  # 0 - exclude low quality data
  27                                    # 1 - include low quality data
  28 a b c d e f g h i j                # Extraction flags
  29 
  30 Flags control the out format and additional extraction filtering.
  31 Flag meaning:
  32 a) 0 - "short" output format (energies in eV), 1 - "long" output
  33    format (energies in eV), 2 - "model" output format, 3 - "short"
  34    format (energies in cm^-1), 4 - "long" output format (energies
  35    in cm^-1)
  36 b) 1 - select only lines with known radiative damping constant
  37    0 - ignore this condition
  38 c) 1 - select only lines with known Stark damping constant
  39    0 - ignore this condition
  40 d) 1 - select only lines with known van der Waals damping constant
  41    0 - ignore this condition
  42 e) 1 - select only lines with known Lande factors
  43    0 - ignore this condition
  44 f) 1 - select only lines with known term designation
  45    0 - ignore this condition
  46 g) 1 - output extended van der Waals damping constants if
  47        available
  48    0 - convert extended van der Waals damping to a standard
  49        constant
  50 h) Not yet implemented
  51    1 - output detailed Zeeman pattern if available
  52    0 - do not output detailed Zeeman pattern
  53 i) Not yet implemented
  54    1 - output extended Stark constants if available
  55    0 - do not output extended Stark constants
  56 j) 1 - output all wavelengths in vacuum
  57    0 - convert wavelengths longward of 200nm to air
  58 
  59 The default value for all the flags is 0.
  60 
  61 1.2. VALD3 file access and unkompress3
  62 
  63 PRESELECT uses a set of subroutines written in C to access the
  64 VALD data files. The entry points used by PRESELECT are: UKOPEN
  65 (opening data files), UKREAD (positioning and reading the first
  66 data block), UKNEXT (reading the next data block) and UKCLOSE
  67 (closing data files). Version 3 of decompression routines
  68 includes two new features compared to the previous versions.
  69 The first is the ability of unkompress3 to determine byte order
  70 of the computer in the run-time. This removes the need to edit
  71 a makefile when porting VALD to a new platform. The second
  72 is obviously the compliance with the new record format used in
  73 VALD3.
  74 
  75 1.3. Output structure and formats
  76 
  77 The output of PRESELECT is sent to standard output and consists
  78 of 3 parts. The first line contains the name of the VALD
  79 configuration file (without quotes). The second line is an
  80 interpretation of the flags used for extraction using 2-symbol
  81 tags. The format and the possible values are as follows:
  82 
  83 1 2 3 4 5 6  <- tag number
  84 Sf------eVAi <- default value corresponding to flag=0
  85 MfEwZpEscmVa
  86 Lf
  87 
  88 Explanations:
  89 
  90 1st tag: Sf/Mf/Lf - output is in short/model/long format
  91 2nd tag: Ew - output contains extended van der Waals constants
  92 3rd tag: Zp - output contains detailed Zeeman pattern
  93 4rd tag: Es - output contains extended Stark constants
  94 5th tag: eV/cm - output contains energies in eV/cm^-1
  95 6th tag: Ai/Va - for lines redward of 200nm output contains
  96               wavelengths in air/vacuum
  97 
  98 2. Limitations
  99 
 100 PRESELECT has a number of configurable options set at compilation.
 101 These point to the VALD list of species and restrict maximum sizes
 102 of internal arrays.
 103 
 104 2.1. Include files
 105 
 106 An include file "VALD_home_path" set a global character variable
 107 VALDHM the absolute path to the VALD home directory on a given
 108 installation (no slash terminator).
 109 An include file "VALD_species" assigns the relative path and file
 110 name of the VALD list of species to the global character variable
 111 VALD_SPECIES and the number of entries in the list of species is
 112 assigned to the global integer variable VALD_sp_list_size.
 113 Normally those two include files should be generated during make
 114 (see the Makefile in PRESELECT directory).
 115 
 116 2.2. Built-in restrictions
 117 
 118 The maximum number of simultaneously open files is specified as a
 119 global integer parameter NF. This parameter is explicitly set
 120 inside PRESELECT (which is bad) and should instead be set at make
 121 according to the corresponding parameter of the operating system.
 122 Setting NF larger than the limit of the OS may result in run-time
 123 fatal error.