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tabhist - histogram plotter and gaussian fit for tabular data
tabhist plots a histogram and computes
the first 4 moments of points obtained from an (set of) column(s) from
an ascii table(5NEMO)
. It calculates the mean, dispersion, skewness and
kurtosis. It then plots the data in the form of a histogram, optionally
with a ’best’ gaussian fit and residuals. It can also plot a cumulative histogram
of the data (see also tabtrend(1NEMO)
The median is also optionally computed,
for which an alternate sorting routine can be selected (if available).
If multiple columns are used, they are appended to each other and treated
like a single long column. If you need simple statistics for multiple columns,
use tabstat instead.
Using the nsigma keyword, outliers can be removed
and statistics re-computed.
The following parameters are recognized
in any order if the keyword is also given:
Points that fall
exactly on the boundary of a bin, are added to the right side. Another way
of saying is that a cell includes the left side, but is open ended on the
right side, i.e. [---). Note this behavior is exactly opposite that of SM’s behavior,
which was used to compare results.
- input file, in tabular
format [no default].
- column(s) from which the (X) values are
taken. Multiple columns can be given in the usual nemoinp(3NEMO)
for integers. [default 1].
- Minimum value along X-axis to include
[default: autoscaling on minimum of datapoints].
- Maximum value
along X-axis to include [default: autoscaling on maximum of datapoints].
- If one number is given, it is the number of (equal size) bins
between min and max. If more than one number is given, they are the bin
edges (thus one more than the number of bins need to be supplied). [default:
- Maximum count value per bin plotted along the Y-axis
- Maximum number of lines allowed to
read from datafile, if the data comes from a pipe as supposed from file.
A regular file will use the number of lines in the file as default. [Default:
- Take log of Y-axis? This option is really redundant, since tabmath(1NEMO)
can handle any transformation [default: f].
- Label along the
X-axis [default: value].
- Label along the Y-axis [default: N or
- Random verbiage, will be plotted along right top
of plot for identification [default: none]. The left top will contain the
- Table output? If false, a plot using your current
device will be given. If true, a simple ascii version of a histogram
is shown. The default choice of bins=16 keeps all the information on a simple
80*24 screen. [Default: f]
- If true, plot output will contain a
gaussian fit. The "best" gaussian fit is the one that has the same mean,
dispersion and integrated area as the data. [Default: t].
true, the residual (data - fit) will be plotted as a dashed line. [Default:
- Plot a cumulative histogram instead. If set, the keywords gauss,
residual, and ylog are automatically re-set to false. [Default: f].
- Compute median too? This can be timeconsuming for large numbers of points.
- Fast median calculator in case N is large. No sort
will be used, but instead an iterative O(N) method will be used. [Default:
f]. robust=t|f Use a robust estimator to remove outliers before taking statistics
again. [Default: f].
- Also compute the Mean Absolute Deviation (MAD).
- Dual pass over the data, subtracting the mean. This
can be important if the data have a large average value with a small spread
around the mean. Notice that in this mode the mean is subtracted but never
added to the min/max/mean/median etc. Default: f
- Delete points
more than nsigma times the sigma from the mean. After each point sigma and
mean are recomputed. [Default: none]
http://arxiv.org/ps/0807.4820 (choosing the binning for a histogram)
xx-mar-88 V1.0: created PJT
15-Apr-88 V1.1: higher order moments, Y scale PJT
1-jun-88 V2.0: new name, code same PJT
28-oct-88 V2.0a: updated doc + labels plotting done PJT
13-nov-93 V2.7: added gaussian model + residuals PJT
11-jul-96 V2.8: log scale is now 10-based, not e PJT
12-apr-97 V3.0: added cumulative option PJT
24-apr-98 V3.0a: fix median calculation for restricted range PJT
22-dec-99 V3.1a: optional median, fix N=1 reporting bug PJT
24-jan-00 documentation updated with program PJT
7-jun-01 3.2: added nsigma, corrected man page options PJT
7-may-03 4.0: multiple columns allowed PJT
28-jan-05 5.0: separate xmin/xmax=, added sort=, fix median if nsigma PJT
1-jun-10 6.0: bins= now allowed to have manual edges PJT
22-aug-12 6.2: added torben= option for fast large-N median PJT
16-jan-14 6.4: added mad= PJT
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