[R] substitution of the ASCII character "squared" AKA "^2" AKA (alt+0178) with a tractable one

[ottorino]

Deae R helpers,
the problem I'm facing today is related to the manipulation of a string.

The string is coming from a a porosimeter, whose control is under a
complicate set-up of two computers

One (running on DOS) is controlling directly the hardware, while the
other (running on win XP) which process the data is connected to the
first one via serial. I get the data from this last computer.

The string I'm trying to process comes from a command like this

> myString <- readLines(path.to.file, 150)[78]

and looks like this

> [1] "(MPa)\t(mm3)\t(nM)\t(mm3/g)\t(mm3/g)\t(%)\t(m\xb2/g)\t"

where "\xb2" is the alt+0178 ASCII character

My problem is to find out the regexp to substitute the ASCII 0178 with a
simple "2" 

No problem with, say

 gsub('\t',';', myString)

[1] "(MPa);(mm3);(nM);(mm3/g);(mm3/g);(%);(m\U3e32623c/g);"

which incidentally change the "\xb2" to "\U3e32623c", 

but I cannot find a way to search and substitute for "\xb2".

I've tried many combinations such as
gsub('\xb', ...
gsub('\\xb', ...
gsub('\\xb2', ...
gsub('\xb2', ... etc

without success.

This is surely due to my ignorance of regexp, but I suspect something
arduous here (at least for me !!).

Further than this, consider that I'm running a Linux box and that I have
to transfer the code to a mac.......

I've tried also to see if it possible to change that string at the
source, but it is possible only on manual basis, quite inconvenient if
you have to process many files.

Any help ? I'm quite discouraged ...


-- 
Ottorino-Luca Pantani, Università di Firenze
Dip.to di Scienze delle Produzioni Vegetali,
del Suolo e dell'Ambiente Forestale (DiPSA)
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