Grapher 14 and newer offer a direct spline smoothing option for line plots. To smooth a line plot:
- Select the plot in the Object Manager
- In the Property Manager, select the Line tab.
- Check the Smooth line check box.
- Adjust the Smooth tension to obtain the desired smoothing. This can be a value between 1 and 0, where 1 is no smoothing and 0 is maximum smoothing.

Left: A line plot with no smoothing applied. Right: The same line plot with smoothing applied.
Grapher 13 and previous:
There is not a direct way to smooth a line in Grapher, but there is a workaround. You can add a spline smoothing fit curve to the plot, and then either turn off the visibility of the original plot, or export the fit curve data and create a line plot from that data.
To add a spline smoothing fit curve:
- Select the Line/Scatter Plot.
- On the Plot page of the Property Manager, click the Add/Edit button next to Fit curve.
- In the Fits dialog, select Spline smoothing from the Available fits dropdown list.
- Click Add.
- Click OK.
- If necessary, select the Fit curve and adjust the Spline tension factor and/or Number of points in the Property Manager.
- If desired, uncheck the Line/Scatter Plot in the Object Manager to make it invisible.
- To export the fit data, select the Fit, and click the Graph Tools | Plot Tools | Export Data command.
Updated March 7, 2019
Comments
3 comments
It is understandable, but it would be better to have explicit a smoothing option.
Hi Konstantin,
Thanks for your feedback! I've added your vote to our suggestion file for the ability to smooth a line plot.
Thanks,
Leslie
Thanks, Leslie....
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