why the label "size" and "face" command does not work? ggplot grouped bar plot-CodePudding

I have the following data set in a csv file, and would like to adjust the size/face of the y axis label, but the command does not work (it only works to change the label, so I can change 'mg/kg' to anything else):

facet   group   oxidation   value
nZVI    DW  Fe(II)  0.319152
nZVI    RW  Fe(II)  5.0832
nZVI    DW  Fe(III) 8.39736
nZVI    RW  Fe(III) 9.3168
nZVI-BC DW  Fe(II)  0.596304
nZVI-BC RW  Fe(II)  7.09764
nZVI-BC DW  Fe(III) 14.1696
nZVI-BC RW  Fe(III) 9.88236
Fe/FeS-BC   DW  Fe(II)  0.382658
Fe/FeS-BC   RW  Fe(II)  42.687
Fe/FeS-BC   DW  Fe(III) 5.4791
Fe/FeS-BC   RW  Fe(III) 4.743
BC  DW  Fe(II)  2.5047
BC  RW  Fe(II)  17.76875
BC  DW  Fe(III) 20.2653
BC  RW  Fe(III) 10.66125
Control DW  Fe(II)  1.457266
Control RW  Fe(II)  20.992
Control DW  Fe(III) 24.47792
Control RW  Fe(III) 11.008

and the code I am using:

 e.data <- read_csv('Grouped stack bars.csv')

 e.data <- mutate(e.data,
             facet = parse_factor(facet,
                                  levels = c('Control',
                                             'nZVI',
                                             'nZVI-BC',
                                             'Fe/FeS-BC',
                                             'BC')))

  ggplot(e.data,                         
    aes(x = group,
       y = value,
       fill = oxidation))   
 geom_bar(stat = "identity",
       position = "stack")  
facet_grid(~ facet)   
theme_bw()  
labs(y = paste('mg/kg'), size = 33, face = 'bold',
   x = NULL)

CodePudding user response：

The labs function can control the text that will appear in various important plot parts, like the title, subtitle, caption, and axis labels for x and y. But it doesn't do any formatting. For that you want the theme() function. Look up ?theme to see all the options (many!). You probably want theme(axis.title.y = element_text(size = 33, face = "bold")).

PS -- btw, it's important to put any theme(...) specifications after the theme_bw() line. theme_bw() is essentially a shortcut for a long list of theme(...) specifications, so if you want to overwrite those with customizations, those changes should come afterwards, otherwise it'll just go with the last specifications received, ie the defaults in theme_bw().