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Small Angle Scattering

DATOP manual


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Table of Contents


The following sections shortly describe how to run DATOP from the command-line on any of the supported platforms, the required input and the produced output files.


DATOP is a tool for arithmetic operations on 1D SAXS data. It is used e.g. for buffer subtraction, for scaling against concentration, for the subtraction of a constant term etc.

Running datop


$ datop <OPERATOR> <FILE> <FILE|X> [-o FILE]

Command-line arguments and options

Argument OPERATOR may be one of: ADD, SUB, MUL, DIV, NORM (case insensitive). DATOP requires two command line arguments where FILE is a data filename, possibly with relative or absolute path components. Instead of a filename, one of the FILE arguments may be '-' to read data from stdin. The second <FILE> argument may also be a numeric constant X.

DATOP recognizes following command-line options:

Short optionLong optionDescription
-o --output FILE Relative or absolute path to save the result; if not specified, the result is printed to stdout.
-v --version Print version information and exit.
-h --help Print a summary of arguments and options and exit.

datop input files

FILE must contain three columns: scattering vector, experimental intensity, experimental errors.

datop output files

The produced output file contains the result of the arithmetic operation.


Subtraction of the buffer (background):

$ datop SUB sample.dat background.dat -o subtracted.dat

Scaling against concentration:

$ datop DIV subtracted.dat 1.23 -o subtracted.dat

When using a negative constant, one needs to pass "--" before the arguments:

$ datop -o result.dat -- MUL subtracted.dat -1.0

  Last modified: April 11, 2013

© BioSAXS group 2013