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- Subscript letters in ggplot axis label 2 answers
I need an axis label in ggplot2 which reads "Assimilation (μmol CO2 m-2 s-1)" with the 2 of CO2 as subscript and the -2 and -1 as superscript. Thanks.
You could try
library(ggplot2)
qplot(uptake, data = CO2) +
xlab(bquote('Assimilation ('*mu~ 'mol' ~CO[2]~ m^-2~s^-1*')'))
来源：https://stackoverflow.com/questions/27445452/superscript-and-subscript-axis-labels-in-ggplot2