.. C-Munipack - User's manual Copyright 2012 David Motl Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. $Id: batch_processing.rst,v 1.1.1.1 2012/08/12 16:57:42 dmotl Exp $ .. index:: pair: batch; processing .. batch-processing: Batch processing ================ Repetitive challenge with reduction of CCD observation is in treating a large number of files. To do this job effectively, it is necessary to execute each reduction step for all frames in subsequent manner. This issue is inconsiderable namely for calibration of CCD frames - the calibration data should be fetched into the memory only once and then applied to all frames. Thus one need to execute an user command for a large set of input files. One straightforward way in processing large batch of frames is writing the names of input files as separate command-line arguments. More shrewd users would use the wild-card notation, but it doesn't work in more complicated situation. There is yet another way - using directory files. The directory file is a simple text file. Each line consists of a file path or name. Such file can be obtained using simple command. On GNU/Linux:: ls ??? > dirfile.txt On Windows:: dir /b *.st7 > dirfile.txt If the files are placed not in the current working directory, you have to specify the proper path in full or shortened form relative to the current working directory. It is not allowed to use the wild-card notation here. Use the :option:`-i` option to instruct the program to read the file. When a program produces a number of files, it is also necessary to assign a distinct name for each output file. By default, the output files are stored to the current working directory. Their names are derived from the command name followed by a sequential number starting by 1. By means of the command-line options, it is possible to override this behavior. The :option:`-o` option sets the format string; it may contain a path where the files shall be stored to. Special meaning has a sequence of question marks, it is replaced by the ordinal number of a file indented by leading zeros to at least the same number of decimal places as the number of the question marks. By means of the :option:`-i` option, you can modify the ordinal number of the first frame. The following command writes its output to files :file:`out010.fts`, :file:`out011.fts` and :file:`out012.fts`:: darkbat -o out???.fts -i 10 dark.fts in001.fts in002.fts in003.fts If you are going to use the files produced by one command as the input files of the subsequent operation, you can ask the former to make a directory file for you by including the :option:`-g` option followed by a file name.