adding line annotation at a specfic data point

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Wed, 04/20/2016 - 01:27 pm

Good afternoon, ss there a way to make line annotations at a specific x value on a graph with the point annotated? I would like to have annotations as in the figure. Thank you.
Hi jsingh,

yes this is possible using the Tag operation.

Make/O data = p
Display data
Tag/C/N=text0/X=1.90/Y=23.08 data, 10, "fancy point"

April 20, 2016 at 02:32 pm - Permalink

Also for drawing lines at specific positions you can use the drawing tools (show the toolbox on a graph with ctrl+t). Draw a line somewhere on the graph. Then switch to the cursor and double click that created line. In the appearing menu you can select the coordinate system for x and y independently. For a line like in you example you may want to set the x coordinates to 'Axis bottom' and dial in the desired value for the start AND end point of your line. The y coordinates can be left to 'plot relative', which means the space inside your plot area (where the data is plotted, without the outside labels etc. 0 equals the top edge and 1 equals the bottom edge). Be aware that dragging the line afterwards will change the values anyway, but resizing the graph or changing the axis range will properly move the line with the x position. To create multiple such lines I recommend to duplicate the first line (ctrl+d) to have everything already set properly so that you only need to change the values. Of course you can also use commands in the command line.

April 20, 2016 at 11:00 pm - Permalink

jsingh wrote:
Good afternoon, ss there a way to make line annotations at a specific x value on a graph with the point annotated? I would like to have annotations as in the figure. Thank you.

I would strongly recommend Help->Getting Started. It includes a Guided Tour that takes you step-by-step through a number of common tasks in Igor, including adding a tag to a data point. It takes some time, but will save you much more time by making your use of Igor more efficient.

John Weeks
WaveMetrics, Inc.
support@wavemetrics.com

April 21, 2016 at 10:32 am - Permalink