Perform basic statistics on a KMOS-conform fits-file
This recipe performs basic statistics on KMOS-conform data-frames of type F2D, F1I, F2I and F3I either with or without noise and RAW. Optionally a 2D mask can be provided to define a region on which the statistics should be calculated on (mask 0: exclude pixel, mask 1: include pixel). A mask can’t be provided for statistics on F1I frames.
The output is stored in a vector of length 11. The vector represents following values:
- Number of pixels
- Number of finite pixels
- Mean
- Standard Deviation
- Mean with iterative rejection (i.e. mean & sigma are calculated iterati- vely, each time rejecting pixels more than +/-N sigma from the mean)
- Standard Deviation with iterative rejection
- Median
- Mode (i.e. the peak in a histogram of pixel values)
- Noise (a robust estimate given by the standard deviation from the nega- tive side of the histogram of pixel values)
- Minimum
- Maximum
The same numerical operations are applied to the noise as with the data itself.
DO DO KMOS
category group Type Explanation Required #Frames
-------- ----- ----- ----------- -------- -------
<none or any> - F3I or The datacubes Y 1
F2I or
F1I or
F2D or
B2D or
RAW
<none or any> - F2I or The mask N 0,1
F2D or
B2D or
RAW
DO KMOS
category Type Explanation
-------- ----- -----------
STATS F1I Calculated statistics parameters
Create an object for the recipe kmo_stats.
import cpl
kmo_stats = cpl.Recipe("kmo_stats")
The extension the stats should be calculated of. Zero is default and calculates the stats of all extensions (long; default: 0) [default=0].
The positive rejection threshold for kappa-sigma-clipping (sigma). (float; default: 3.0) [default=3.0].
The negative rejection threshold for kappa-sigma-clipping (sigma). (float; default: 3.0) [default=3.0].
The number of iterations for kappa-sigma-clipping. (long; default: 3) [default=3].
The following code snippet shows the default settings for the available parameters.
import cpl
kmo_stats = cpl.Recipe("kmo_stats")
kmo_stats.param.ext = 0
kmo_stats.param.cpos_rej = 3.0
kmo_stats.param.cneg_rej = 3.0
kmo_stats.param.citer = 3
You may also set or overwrite some or all parameters by the recipe parameter param, as shown in the following example:
import cpl
kmo_stats = cpl.Recipe("kmo_stats")
[...]
res = kmo_stats( ..., param = {"ext":0, "cpos_rej":3.0})
See also
cpl.Recipe for more information about the recipe object.
Please report any problems to Alex Agudo Berbel. Alternatively, you may send a report to the ESO User Support Department.
This file is part of the KMOS Instrument Pipeline Copyright (C) 2002,2003 European Southern Observatory
This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, 51 Franklin Street, Suite 500, Boston, MA 02110-1335 USA
Code author: Alex Agudo Berbel <usd-help@eso.org>