Measure distance travelled using rotary encoders

odometer:
Why not just use multiplication and/or division?

Anyway, you have to decide whether to use an int, long, or float. The map() function will not work on floats.

map() - Arduino Reference

By the way, since you mention inches, I suppose you are American. And let's face it, Americans are not exactly known for their numeracy skills.

Yes, American (Texican), here. No, for this project map() is not appropriate. But if you have never used it, and are unaware, it uses long math. That gives a range of over 4 billion. I think most projects would not suffer with a range of 4 billion.

I have a suspicion that since you dislike inches, you may be from Vietnam. I was over there in the late 1960s. Maybe I met some of your family.
có một ngày tốt

map() can only deal with whole numbers. So if the OP needs numbers such as 2.5 (meters or yards or whatever), map() is not right for him.

Besides, if he is dealing in feet and inches, that has problems of its own.
Relevant: Lidar Lite Measure in Ft, In. - Project Guidance - Arduino Forum

And, no, I don't have a problem with inches themselves. It's the fractions I have a problem with. That and having to restart your count of inches every time you have enough of them to make a foot.

For the record, I'm from the northeastern U.S. I have seen survey maps for places around here: they express distances in feet and hundredths of a foot (no inches). I don't know what units they use for land surveying in Texas (feet? yards? chains?), but I am guessing that they are decimalized. (Of course, this is just for measuring land. You would still express your height in feet and inches, do carpentry in inches and halves/quarters/eighths of an inch, etc.)

Another example of decimalization around here is when I go to a grocery store deli. The scales are in pounds and hundredths of a pound (no ounces). If you want to mess with the deli clerk's mind, ask for four tenths of a pound of something. (Why not? The scale is decimal...) Quite likely, the clerk will have no idea what you mean, and that is what I mean by innumeracy.

@jack wp:

For your amusement: Confusing Tape Measures | Contractor Talk - Professional Construction and Remodeling Forum

@odometer, Thanks for the amusing link.
I think I/we have gotten a bit off topic here.
I apologize to the OP (original poster).
Did your questions get answered, or do you have more questions?

Confusing Tape Measures | Contractor Talk - Professional Construction and Remodeling Forum

But what are the little lines between the nice fractions?