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Statistics - calculate statistics of a dataset


aststatistics [OPTION...] ASTRdata


Statistics is part of GNU Astronomy Utilities 0.8. Statistics will do statistical analysis on the input dataset (table column or image). All blank pixels or pixels outside of the given range are ignored. You can either directly ask for certain statistics in one line/row as shown below with the same order as requested, or get tables of different statistical measures like the histogram, cumulative frequency style and etc. If no particular statistic is requested, some basic information about the dataset is printed on the command-line.

For more information, please run any of the following commands. In particular the second contains a very comprehensive explanation of Statistics's invocation: expected input(s), output(s), and a full description of all the options.

All options and their values:
$ aststatistics -P
Inputs/Outputs and options:
$ info aststatistics
Full section in manual/book:
$ info Statistics
Full Gnuastro manual/book:
$ info gnuastro

If you couldn't find your answer in the manual, you can get direct help from experienced Gnuastro users and developers. For more information, please run:

$ info help-gnuastro

Statistics options:

-c, --column=STR
Column name or number if input is a table.
-g, --greaterequal=FLT
Only use values greater-equal than this.
-h, --hdu=STR/INT
Extension name or number of input data.
-I, --ignorecase
Ignore case in matching/searching columns.
-l, --lessthan=FLT
Only use values less than this.
-Q, --qrange=FLT[,FLT]
Quantile range: one (from Q to 1-Q) or two.
-r, --refcol=STR
Reference column name or number.
Select column(s): `name', `unit', `comment'.
Micro-seconds to wait for standard input.
Tessellation (tile grid):
Tile IDs in an image, the size of input.
-F, --remainderfrac=FLT
Fraction of remainder to split last tile.
-i, --interpolate
Interpolate over blank tiles to fill them.
No. of neighbors to use for interpolation.
Only interpolate over the blank tiles.

-M, --numchannels=INT[,..] No. of channels in dim.s (FITS order).

Display 1 element/tile, not full input res.
Work (not tile) over channel edges.
-Z, --tilesize=INT[,INT]
Regular tile size on dim.s (FITS order).
-D, --dontdelete
Don't delete output if it exists.
-K, --keepinputdir
Keep input directory for automatic output.
-o, --output=STR
Output file name.
Table format: `fits-ascii', `fits-binary'.
Single value measurements
-d, --std
Standad deviation.
-E, --median
-m, --mean
Mode quantile (see --mode)
Mode symmetricity (see --mode).
Value at mode symmetricity (see --mode).
Number (non-blank).
-O, --mode
Mode (Appendix C of arXiv:1505.01664).
Quantile function (multiple values acceptable).
-u, --quantile=FLT[,...]
Quantile (multiple values acceptable).
Particular calculation
Print an ASCII cumulative frequency plot.
-A, --asciihist
Print an ASCII histogram.
-C, --cumulative
Save the cumulative frequency plot in output.
-H, --histogram
Save the histogram in output.
Save the histogram and CFP of the mirror dist.
-s, --sigmaclip
Overall sigma-clipping (see `--sclipparams')
-t, --ontile
Single values on separate tiles, not full input.
-y, --sky
Find the Sky and its STD over the tessellation.
Sky and Sky STD settings
Store steps in `_sky_steps.fits' file.
Don't write input's blanks in the Sky output.
-k, --kernel=STR
File name of kernel to convolve input.
HDU/extension name or number of kernel.
Max. mode and median quantile diff. per tile.
Max. distance (error multip.) to find mode.

--outliersclip=FLT,FLT Sigma-clip params for qthresh outliers.

Multiple of sigma to define outliers.
Sigma clip: Multiple, and tolerance/number.
Sky: flat kernel width to smooth interpolated.
Histogram and CFP settings
Height of ASCII histogram or CFP plots.
Set min/max of bins manually, not from data.
Scale such that the maximum bin has value of one.
No. of bins in ASCII histogram or CFP plots.
No. of bins in histogram or CFP tables.
-n, --normalize
Set sum of all bins to 1.
Shift bins so one bin starts on this value.
Operating modes:
-?, --help
give this help list
BibTeX citation for this program.
Read configuration file STR immediately.
Do not parse any more configuration files.
Minimum bytes in array to not use ram RAM.
-N, --numthreads=INT
Number of CPU threads to use.
Only run if the program version is STR.
-P, --printparams
Print parameter values to be used and abort.
-q, --quiet
Only report errors, remain quiet about steps.
-S, --setdirconf
Set default values for this directory and abort.
give a short usage message
-U, --setusrconf
Set default values for this user and abort.
-V, --version
print program version

Mandatory or optional arguments to long options are also mandatory or optional for any corresponding short options.

GNU Astronomy Utilities home page:


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Copyright © 2015-2018, Free Software Foundation, Inc. License GPLv3+: GNU General public license version 3 or later.
This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.

Written/developed by Mohammad Akhlaghi


The full documentation for Statistics is maintained as a Texinfo manual. If the info and Statistics programs are properly installed at your site, the command
info Statistics

should give you access to the complete manual.

December 2018 GNU Astronomy Utilities 0.8