Set source and background data using the S-lang module function in Sherpa.
Integer_Type set_data([Integer_Type,]Array_Type)
Integer_Type set_back([Integer_Type,]Array_Type)
Success/Error Return Values: 1/0
Arguments:
(1) Dataset number (default 1)
(2) An array of source/background data amplitudes
Note that if only one argument is provided, it is assumed to be an
array, and the dataset is assumed to be dataset 1.
The set_data
and set_back functions allow the user
to assign new source and background data amplitudes (for example
number of counts)
(i.e., the y values in
y = f(x))
to Sherpa datasets.
Note that:
-
The input array length must match the number of bins in the
filtered dataset;
consequently, if one's goal is to use these functions in data manipulation,
it is important not to change the
filter in Sherpa between any call to, e.g.,
get_data and set_data!
-
The input array is typecast to match the type of its associated
dataspace (see, e.g., set_axes for a
definition of dataspaces).
For instance, if dataset 3 is of Double_Type, then when
set_data(3,<array>) is run, the array is typecast to
Double_Type if necessary.
Retrieve data from Sherpa, process it,
and replace:
sherpa> DATA spec.dat
sherpa> d = get_data(1)
sherpa> print(d)
2
8
12
20
18
27
....
sherpa> d -= 10
sherpa> print(d)
-8
-2
2
10
8
17
....
sherpa> () = set_data(,d)
In this example, data are read into Sherpa in the
first command and the
counts values are retrived using get_data.
Then, 10 counts are subtracted off every element of the array d; the
new array is then sent to Sherpa, where it overwrites
the old array. print command shows the first numbers of the array values.
- chandra
-
guide
- sherpa
-
autoest,
back,
berrors,
bsyserrors,
coord,
data,
dataspace,
fakeit,
feffile,
group,
guess,
is_subtracted,
load,
load_arf,
load_ascii,
load_back_from,
load_backset,
load_dataset,
load_fitsbin,
load_image,
load_inst,
load_inst_from,
load_pha,
load_pha2,
load_rmf,
read,
set_analysis,
set_axes,
set_backscale,
set_coord,
set_exptime,
set_subtract,
set_weights,
setback,
setdata,
subtract,
ungroup,
unsubtract,
use
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