datregrid
Manual
The following sections briefly describe how to run DATREGRID from the command- line, the required input and the produced output files.
Introduction
DATREGRID is a tool to modify the angular grid of experimental SAS data (.dat) files. Available modifications are:
- replace: replaces the angular grid of one file with that of a template
- scale: scale the angular grid by a factor, e.g. to convert from \(\AA^{-1}\) to \(\text{nm}^{-1}\) or vice versa
- template-avrg: for each angular grid point of a template, average the nearest data points of the source data
- template-copy: for each angular grid point of a template, find the closest data point of the source data
- join: join a number of data points by averaging
- logarithmic: convert the source grid to logarithmic scaling
All template grids must be less dense than the source data. There is no interpolation of data points.
Running datregrid
Usage:
$ datregrid [OPTIONS] <SASDATA>
OPTIONS known by DATREGRID are described in next section, the required argument FILE in the section on input files.
Command-Line Arguments and Options
DATREGRID requires the following command line arguments:
| Argument | Description |
|---|---|
| SASDATA | Exactly one experimental SAS data (.dat) |
| file. |
Absolute as well as relative path to data files are accepted. Instead of a file name, the argument may be given as ‘-‘ to read data from stdin.
DATREGRID recognizes following command-line options:
| Short option | Long option | Description |
|---|---|---|
| -r | --replace <FILE> | Replace input s-axis by the one read from FILE. |
| -s | --scale <FACTOR> | Scale the angular axis by FACTOR. |
| --template-avrg <FILE> | Use s-axis from FILE, average nearby neighbours | |
| --template-copy <FILE> | Use s-axis from FILE, copy nearest neighbour to output | |
| -j | --join <N> | Join N points by averaging. |
| -l | --logarithmic <N> | Logarithmic binning to N total points |
| -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, options, and exit. |
datregrid input files
DATREGRID expects experimental SAS data (.dat) .
datregrid output files
DATREGRID writes the same experimental SAS data (.dat) , but with the angular grid transformed by the selected option.
Examples
Preparation of bsa_beg.dat and bsa_end.dat for merging using template.dat as a template and merging them with DATMERGE.
$ datregrid bsa_beg.dat -t template.dat -o bsa_beg_regrided.dat
$ datregrid bsa_end.dat -t template.dat -o bsa_end_regrided.dat
$ datmerge bsa_beg_regrided.dat bsa_end_regrided.dat -o bsa_regrided_merged
Changing angular units of the SAXS data file from inverse Angstroms to inverse nanometres.
$ datregrid bsa_angstrom.dat -s 10 -o bsa_nm.dat
Replace s-axis of SAXS data file with the new one.
$ datregrid bsa.dat -r new_axis.dat -o bsa_new_axis.dat