Defines an expression to be used to specify the
statistical errors for source data.
sherpa> ERRORS [<dataset range> | ALLSETS] = <errorExpr>
where <dataset range> = #, or more generally #:#,#:#,..., such that #
specifies a dataset number, and #:# represents an inclusive range of
datasets; one may specify multiple inclusive ranges by separating them
with commas. The default dataset is dataset 1.
The error expression, <errorExpr>, may be composed of one, or
more (algebraically-combined) of the following elements:
| DATA | An input dataset |
| numericals | Numerical values |
| operators | + - * / ( ) |
A few things to note:
-
Error expressions cannot be defined without first reading in
a source dataset.
-
The errors can be specified in an input file;
see READ
ERRORS for more information.
-
If the errors are not defined using ERRORS or input
using READ ERRORS, then they are
computed as defined for the current statistic;
see the documentation on the command
STATISTIC.
See the related command SYSERRORS.
The errors are accessible to the Sherpa/S-Lang module
user via the functions
get_errors and
set_errors.
Define an expression to be used for the errors. They are set to
one-half of the data value in each bin.
sherpa> DATA example.dat
sherpa> ERRORS = (0.5)*(DATA)
Define an expression to be used for the errors. They are set to be
the sum of the datum and 2.7 in each bin.
sherpa> DATA example.dat
sherpa> ERRORS 1 = DATA + 2.7
- sherpa
-
berrors,
bsyserrors,
compute_errors,
compute_statistic,
covariance,
ftest,
get_paramest,
get_paramestint,
get_paramestlim,
get_paramestreg,
goodness,
interval-projection,
interval-uncertainty,
list_paramest,
mlr,
projection,
region-projection,
region-uncertainty,
restore_paramest,
run_paramest,
run_paramestint,
run_paramestlim,
run_paramestreg,
set_errors,
set_syserrors,
staterrors,
syserrors,
uncertainty
|
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