Can Axis Labels Mismatch Axis Tick Marks?

[djbateman]

Is there a way to display axis tick marks using one measurement but display labels based on a different measurement?

I have been asked to plot a Kaplan-Meier curve with the x-axis showing tick marks as weeks but labeling in months.  This is not as simple as assuming that a month has exactly 4 weeks.  I am using the formula: MONTHS=(WEEKS*7)/30.4375.  Thus, 8 weeks will not appear as 2 months but rather 1.84 months.  In other words, my labels will be slightly off of my tick marks as I attempt to display below:

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[GraphGuy · Accepted solution]

Here's one trick you could use with gplot ...

You could annotate the monthly labels.

Here's a similar example where the x-axis is by month, and I annotate the year:

Worldwide Browser Popularity

http://robslink.com/SAS/democd59/browser_wars_info.htm

If you want, you can totally suppress the individual tickmark values by using 'value=none' on the axis statement.