9.3.7.14 The (Plot Details) Drop Lines TabPDDialogDropLineTab
You can add drop lines to either axis in any 2D data plot type that incorporates plot symbols, and to any plane in 3D scatter and trajectory graphs.

3D Scatter, 2D/3D Ternary Graph



Direction Control for Drop Lines
For 2D graph in cartesian coordinate, Horizontal or Vertical drop lines are optional.
For 2D ternary and 3D (including 3D Ternary) graph, drop lines Parallel to X/Y/Z Axis are optional.For 3D Scatter/Trajectory graph, Drop Lines tab is available on both Original and XY/ZX/YZ Projection level: On Original level, drop lines on all three directions(parallel to X/Y/Z axis) are optional; but on XY/ZX/YZ Projection level, only two directions along the axes of current panel are optional, such as on XY Projection level, you are only allowed to turn on the drop lines parallel to X and Y axis. For 3D Ternary graph, only drop lines parallel to vertical Z axis(Zh) is available. In contrast, all three directions are allowed to add drop lines for 2D Ternary graph.
Line Style Controls
Select the Horizontal/Vertical or Parallel to X/Y/Z Axis check boxes to display horizontal or vertical lines from each data point symbol to the bottom X or left Y axis. Then select the style, width and color for the dropline with the Style, Width and Color dropdown lists.
Note: When you select Autofrom the Color dropdown lists, Origin uses the color selected from the Symbol Color or the Edge Color buttons on the (Plot Details) Symbol tab.

Drop To Controls
You can use this dropdown list to specify which line(axis line or additional line) or surface(axis panel or surface from 3D data) the current drop lines should be dropped to.
For 2D Scatter/Line graph in cartesian coordinate, four options are available under this dropdown list:
 Auto: This item is selected by default to make drop lines drop to Left X and bottom X axis.
 X/Y=Axis Begin: Make drop lines drop to the left Y Axis/bottom X axis which is at the position X/Y=Min.
 X/Y=Axis End: Make drop lines drop to the right Y Axis/top X axis which is at the position X/Y=Max.
 X/Y=Custom Additional Line:Make drop lines drop to the custom additional line at X/Y=custom value. If there is no additional line, drop lines will follow the Auto behaviors.
For 2D Ternary graph, two target axis lines are available under this dropdown list:
 When drop lines Parallel to X Axis, you are allowed to select Y or X to specify which axis the drop lines should drop to.
 When drop lines Parallel to Y Axis, you are allowed to select X or Z to specify which axis the drop lines should drop to.
 When drop lines Parallel to Z Axis, you are allowed to select X or Y to specify which axis the drop lines should drop to.
For 3D Scatter/Trajectory graph, four options are available under this dropdown list:
 Auto:This item is selected by default to make drop lines drop to X=Min/Y=Max/Z=Min plane.
 X/Y/Z=Axis Begin Plane: Make drop lines drop to the YZ/XZ/XY panel which is at the position X/Y/Z=Min.
 X/Y/Z=Axis End Plane: Make drop lines drop to the YZ/XZ/XY panel which is at the position X/Y/Z=Max.
 Surface:Make drop lines drop to the surface which is created from 3D data. If there is no surface, drop lines will follow the Auto behaviors.
For 3D Ternary Scatter graph, only Parallel to Z Axis is available which can be used to add drop lines along vertical Z axis(Zh).
Show at Specified Points Only
This control can be used to add drop lines at specific data points or at specific x values.
Here, five syntaxes are supported:
 row indices separated by spaces, such as 1 3 5 show drop lines at specified row 1,3,5
 start and end row indices with the number of skipped points, such as 2:0:5 shows 1 row and skip 5 rows, from 2nd row to the end row
 X values with space separators, but need add x= before the values, such as x=3.5 7.8 show at specified X values(3.5 and 7.8)
 row indices stored in another column which can be selected in the dropdown list, such as [Book1]sheet2!col(A) show drop lines at specified rows, with row indices from this selected column
 X values stored in another column which can be selected in the dropdown list, but need add x= before the range, such as x=[Book1]sheet2!col(A) show at specified X values, with X values from this selected column
Please note, when you are adding the drop lines by specifying the X values, if the specified x values are not dropped on the data points, the interpolation will be performed to locate the specified X values at the connect lines between the nearest data points. And, only when the Line Connect had been set to Straight, the drop lines specified by X values will work. See an example as below:
Data Points Display Control
Select the Skip Points check box to display a specified frequency of data points, then type the frequency in the associated text box. This setting also effects the display of the data plot drop lines, symbols, error bars, and data labels.
If n is entered in the Skip Points text box, then only the first out of every n data points will be displayed; the remaining n1 data points will be skipped. But the last data point will always show. If you want to hide the last point, set @SMEP = 0. n must be an integer value greater than or equal to 2. If n = 0 or 1, no point is skipped.
If the plot contains a line plot, then you can use the No Line Break for Skipped Point(s) check box to specify whether to break the line if points are skipped. If this is selected, the line will still be continuous even though the data points are skipped.
