IXTdataset 3d

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An IXTdataset_3d is an object that stores signal and error data against three independent dimensions (the x, y and z axes). Title and label information is also stored. These are used for manipulating and visualising three dimensional data.


Three dimensional plotting can be used to visualise the data and many functions exist to manipulate it given in the user manual


Fields

IXTdataset_3d objects contain the following fields


Field Type Description
base IXTbase Object required for internal use
title char 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)
y real (ptr) Second independent variable data (i.e. y data). If point data this will be the point positions in the y axis. If histogram data, this will be the bin boundaries in the y axis
y_axis IXTaxis object containing the y axis label and units code information
y_distribution logical True if signal is a distribution on y (e.g. counts/spectrum) False if signal is not a distribution on y (e.g. counts)
'z real (ptr) Third independent variable data (i.e. z data). If point data this will be the point positions in the z axis. If histogram data, this will be the bin boundaries in the z axis
z_axis IXTaxis object containing the z axis label and units code information
z_distribution logical True if signal is a distribution on z (e.g. counts/spectrum) False if signal is not a distribution on z (e.g. counts)


Constructing an IXTdataset_3d Object

The constructor for an IXTdataset_3d can be used to create a full IXTdataset_3d object using the following syntax

>> ww = IXTdataset_3d(base, 'title', [signal], [error], s_axis,...
[x], x_axis, [x_distribution], [y], y_axis, y_distribution, [z], z_axis, z_distribution )
  • Size(signal,1), size(error,1), Length(x) must all be equal
  • Size(signal,2), size(error,2), Length(y) must all be equal
  • Size(signal,3), size(error,3), Length(z) must all be equal
  • x, y and z must be one dimensional arrays
  • Signal and error must be three dimensional arrays of size (length(x), length(y), length(z))
  • s_axis, x_axis and y_axis must be properly constructed IXTaxis objects
  • x_distribution, y_distribution and z_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

>> ww = IXTdataset_3d(x, y, z, 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, y and z data
  • Title, s_axis, x_axis, y_axis and z_axis, will contain blank objects
  • x_distribution, y_distribution and z distribution will be FALSE


Changing Values in an IXTdataset_3d 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

>> ww.title = 'mytitle'

will set the title in w to 'mytitle'