1.160 FAQ-817 How do I add drop lines to a 2D line plot?

Last Update: 5/19/2020

Starting with Origin 9.1, you can add drop lines directly to a Line/Line+Symbol plot using controls on the Drop Lines tab of Plot Details dialog.

Double-click on the plot to open Plot Details.
Click on the Drop Lines tab, configure your drop lines. Click Apply or OK.

From Origin 2020b, you can specify adding drop lines at special positions by Show at Specififed Points Only edit box on the Drop Lines tab.

Syntaxes to specify drop line positions...

If you want to...	Syntax	Example
start from Nth point to Mth point, show every Kth points	N:M:K where 0 refers to the last point	start from 1st point to the last, skip every 4 points:`1:0:5`
show points at special values	x/y=specified x/y values, sparated by space	show at x=3.5 5: `x=3.5 5`
show Nth point	N if multi-points, use space to sparate	show at 1st, 3rd and 10th points: `1 3 10`
show at specified rows values from the specified column	range nonation of the indices column	if [Book1] Sheet2!col(A) fills values 1 3 5 10, enter: `[Book1] Sheet2!col(A)` will show drop lines at 1st, 3rd, 5th, and 10th points.
show at spefied X values read from the specified column	x=range nonation of the value column	if [Book1] Sheet2!col(A) fills values 1 3 5 10, enter: `x=[Book1] Sheet2!col(A)` will show drop lines at x = 1, 3, 5, and 10 points.

Prior to Origin 9.1, adding drop lines to a 2D line plot required the following work-around:

Drop Lines tab is only available for Line + Symbol plot type. If you have a Line graph, select Line + Symbol from Plot Type drop-down on bottom-left side of Plot Details dialog to show the Drop Lines tab.
To remove plot symbols for an independent plot, click the Symbol tab and open the symbol gallery (below Preview) and click on an empty cell (bottom of the gallery).
For dependent grouped plots (Edit Mode, Group tab), set Symbol Type to Increment = None, and on the Symbol tab, set Shape to 0 No Symbol.

Keywords:drop lines, line + symbol, symbol, symbol size