IXTdataset 1d
An IXTdataset_1d is an object that stores signal and error data against one independent dimension (the x axis). Title and label information is also stored. These are used for manipulating and visualising a single spectrum.
One dimensional plotting can be used to visualise the data and many functions exist to manipulate it given in the user manual
Fields
IXTdataset_1d objects contain the following fields
| Field | Type | Description |
|---|---|---|
| base | IXTbase | Object required for internal use |
| title | char(allocatable) | Title of the dataset used in plotting |
| signal | real(ptr) | Signal data |
| error | real(ptr) | Standard error |
| s_axis | IXTaxis | object containing the signal axis label and units code information |
| x | real(ptr) | First independent variable data (i.e. x data). If point data this will be the point positions in the x axis. If histogram data, this will be the bin boundaries in the x axis |
| x_axis | IXTaxis | object containing the x axis label and units code information |
| x_distribution | logical | True if signal is a distribution on x (e.g. counts/microsecond) False if signal is not a distribution on x (e.g. counts) |
Constructing an IXTdataset_1d Object
The constructor for an IXTdataset_1d can be used to create a full IXTdataset_1d object using the following syntax
>> w = IXTdataset_1d(base, 'title', [signal], [error], s_axis, [x], x_axis, [x_distribution])
- Length(signal), Length(error), Length(x) must all be equal
- signal, error and x must be one dimensional arrays
- s_axis and x_axis must be properly constructed IXTaxis objects
- x_distribution must be a logical value (1 or 0, TRUE or FALSE)
- base must be a properly constructed IXTbase object
Datasets without title and label information may be constructed using the syntax
w = IXTdataset_1d(x, signal, error)
- signal and error may be omitted. If so, w.signal and/or w.error will contain an array of 0's matching the dimensions of the x data
- Title, s_axis and x_axis will contain blank objects
- x_distribution will be FALSE
datasets can also be made using commands found in input and output functions
Changing Values in an IXTdataset_1d object
The fields in the object are accessible on the matlab command line. Therefore the values of the fields can be changed easily, for instance
>> w.title = 'mytitle'
will set the title in w to 'mytitle'
Examples
Two Identical Scripts to Construct an IXTdataset_1d From a Function
Here, assume that a function my_func is some unusual function of the form
function y = my_polynom(x, pin)
y = pin(1).*x.^6 + pin(2).*x.*sin(x) + pin(3).*x
The function
x = 1:300
y = my_func(x, [2, 3, 2]) % generate y values
title = 'my unusual function'
xaxis = IXTaxis('Independent Variable')
yaxis = IXTaxis('Dependent Variable')
e = zeros(size(x)) % need error values for full construction
w = IXTdataset_1d(IXTbase, title, y, e, yaxis, x, xaxis, false)
dl(w) % plot the data
gives the same results as
x = 1:300
w = IXTdataset_1d(x) % create dataset with blank y and e values
w.title = 'my unusual function'
w.x_axis = IXTaxis('Independent Variable')
w.s_axis = IXTaxis('Dependent Variable')
w = func_eval(w,my_polynom(x,[2 3 2])) or w = func_eval(w,@my_polynom,[2 3 2])
dl(w)
F90 Syntax
use IXMdataset_1d type(IXTdataset_1d):: dataset_1d type(IXTstatus):: status
Fortran Operations
The following operations may be performed on this data type: