public class NFStripChartApp extends Applet
This class supports the generation of Strip Charts, which are ideal for displaying time based data that is periodically updated. Some examples are performance meters, currency tracking, stock tracking, seismograph, and so on. The Strip Chart is designed to make implementing this type of chart easy, fast, and Internet accessible.
The Strip Chart is based on a certain number of "slots" in the X axis. The slots are equally divided into the available graphing space and represent a particular point in time. The rightmost slot contains the newest data, and the leftmost slot has the oldest displayed data. Data in multiple data sets is added synchronously, with one point being extracted from each dataset as each new slot is added.
Note that data is only displayed in the graph after the Update parameter (described below) is passed.
The following standard parameters are supported by this chart:
Background
Header HeaderBox Footer FooterBox LeftTitle LeftTitleBox RightTitle RightTitleBox
DwellLabel DwellBox ActiveClicks ActiveLabels[1-50]
Legend LegendBox LegendItems
LeftAxis RightAxis
Grid GridLine GridAxis
ColorTable
NoteSets NoteSets[1-20] NoteArrow NoteAxis NoteLabel NoteBox
The following parameters are specifically supported by this chart:
DataSets = (dataset1 tuple), (dataset2 tuple),...;
Defines a list of dataset tuples with the following attributes in each tuple:
"Name" - Name assigned to this data set SymColor - Symbol Color SymType - Symbol Type (CIRCLE, SQUARE, DIAMOND, CROSS, TRIANGLEDOWN, TRIANGLEUP, VRECTANGLE) SymSize - Symbol Size (in pixels) SymStyle - Symbol Style (FILLED, OUTLINED) LineType - Line Type (SOLID, DOTTED, DASHED, DOTDASH) LineWidth - Line Width (in pixels) LineColor - Line Color
By default, the Name and SymColor will be used as items in the Legend.
If any of the symbol attributes are undefined, default values will be used.
If the LineType attribute is defined, the data symbols in the given data set will be connected by line segments using the given line attributes.
At most 50 datasets may be displayed.
If a color is not specified in the vector, then the previously specified color will be used. If the color is specified as "null", then a default color will be chosen from the color table. (See the ColorTable parameter.)
If a line color or fill color is assigned "null", then the line or area fill will not be drawn.
DataAxis = (XAxis1, YAxis1), (XAxis2, YAxis2), ...;
The XAxis and YAxis attributes define the specific axis to be used when mapping the X and Y values respectively for each data set defined. The XAxis attribute may be set to BOTTOM or TOP, while the YAxis may be set to LEFT or RIGHT.
AppendDataSet[1-50] = y1, y2, y3, ...;
Defines a list of y values for each dataset defined by the DataSets parameter. The data is appended onto the data queue for the specified dataset. Data is extracted from the queue when an "Update" (described below) statement is passed. If the value "null" is substituted for a y value, the symbol is not drawn for that slot.
StripLayout = (NumberOfSlots, InitialFill, MaxFill, UndefinedString);
Specifies basic strip chart information. The NumberOfSlots parameters identifies how many "steps" there are in the chart's X axis. InitialFill is either LEFT or RIGHT and indicates which side of the chart the data should begin fill from. The MaxFill parameter indicates the maximum number of datapoints that can be simultaneously loaded without loss. The UndefinedString is the string used when a tic is shown but no data for the tic is available.
TopScale = (SlotsPerTic, TicStart, TicStep, AxisType);
BottomScale = (SlotsPerTic, TicStart, TicStep, AxisType);
SlotsPerTic represents the number of slots between tic marks. TicStart and TicStep are only used when automatically generating labels and indicate the first tic value and the numerical increment. AxisType, which can be either STATIC or DYNAMIC controls the behavior of the Axis. With a STATIC axis, the tics never move, and each slot has an associated label. If more labels are added to the axis, the slots (but not tics) will shift. When the DYNAMIC axis type is used, both tics and labels will move synchronously as data is added. STATIC tics are faster than DYNAMIC tics.
TopLabels = "Label1", "Label2", "Label3", ...;
BottomLabels = "Label1", "Label2", "Label3", ...;
Defines the specific labels to be used for the tic marks along the axis. If no labels are defined, they will be automatically generated, based on the TicStart and TicStep values defined in the corresponding axis parameter (i.e. TopAxis or BottomAxis). Labels can be added at any time, and are appended to the end of the label queue.
Update;
Causes one "slot" of data to be extracted from the input data queue for each data set and displayed. Update will also update the axes and configure the dwell labels for the slot (if defined).
Type | Name | Description | Default | ||||
public | NFStripChart | Underlying strip chart object | stripchart |