Series Functions
A series function defines a mathematical relation that associates one destination series
with one or multiple
source series. A series
function always involves two types of series
components: the
position component and the value
component. The series function associates the value component of the
destination series with the value component(s) of the source series via a mathematical function (e.g.
add, subtract, integrate, differentiate, Fourier transform, etc). The data in the value
component of the destination series of the series function are the values of
this mathematical function of the data in the value component(s) of the source
series of the series function. The data in the position component(s) of the
source series of the series function are usually copied directly to the position
component of the destination source of the series function except for the case
of the FFT series function where the data in the position
component are also subject to the so-called time to frequency transform. Sometimes, not all data in the
source series are used in the series function. In such cases, the user selects a
part of the data in the source series by specifying a range for the data in the
position component(s) of the source series - only data in the position
component(s) of the source series that are in this specific
range will be used in the series function. This range of values is called the domain
of the series function.
It is important not to confuse the position/value components of the source
and destination series of a series function with the Position/Value
series components -
the former are used in the series function context to
refer to the roles of the components in the series function while the latter are
used in the series context to refer to the roles of the components in the
specific series. If a series function involves only series with two mandatory Position
and Value series components, the Position series component of the
source and the destination series will be used as the position component
of the series function and the Value series component of the
source and the destination series as the value
component of the series function. If there are more than two mandatory series
components in the source series, the user may specify one as the value component
of the source series of the series function with the Value combo-box of
the Series Function dialog box.
In a series function, the source series
serve as the data source for the destination series. To
apply a series function to the active series, select the series function type on the Series Function
sub menu of the Graph
menu (which is also the context menu of the graph document) to open the Series Function dialog box
with which a new series function can be created and applied to the active series. If the active series
happens to be the destination series of a series function, an
Edit
Function menu command will appear on the Series Function sub menu of
the Graph menu -
selecting it opens the Series Function dialog box
with which the user can edit the series function that produces the active
series.
The current version of DataScene supports the following 20 series functions:
See Also
|
