Remove space between bars ggplot2

Question

This is my code

    ggplot(df, aes(x=timepoint, y=mean, fill=group)) +
            geom_bar(position=position_dodge(.3), colour=\"black\", stat=\"identity\",         


        

Answer 1

Just adjust the widths:

ggplot(df, aes(x=timepoint, y=mean, fill=group)) +
  geom_bar(position=position_dodge(0.9), colour="black", stat="identity", width=0.9, , binwidth=0) +
  geom_errorbar(position=position_dodge(0.9), width=0.85, aes(ymin=mean, ymax=mean+sem)) +
  theme_bw() 

Answer 2

Something like this?

df <- structure(list(group = structure(c(2L, 1L, 4L, 3L), .Label = c("a1.c.ffa.mean Control", 
"a1.d.ffa.mean Dysglyc", "b1.c.ffa.mean Control", "b1.d.ffa.mean Dysglyc"
), class = "factor"), timepoint = structure(c(1L, 1L, NA, NA), .Label = c("Baseline", 
"12W"), class = "factor"), mean = c(1.913509, 2.181959, 2.742249, 
1.50846), sem = c(0.10663114, 0.08360294, 0.07890374, 0.08348542
), p.value = c(0.597738161, 1, 0.007885464, 1), p.value.t = c(0.04408, 
1, 0.2455049, 1)), .Names = c("group", "timepoint", "mean", "sem", 
"p.value", "p.value.t"), row.names = c(NA, -4L), class = "data.frame")

reorder factor levels with

df$timepoint <- factor(df$timepoint, 
                       levels= c('Baseline', '12W'))

plot it

ggplot(df, aes(x=factor(timepoint), y=mean, fill=group)) +
  geom_bar(position=position_dodge(.3), colour="black",
           stat="identity", width=0.3, , binwidth=0) +
  geom_errorbar(position=position_dodge(.3), width=.25,
                aes(ymin=mean, ymax=mean+sem)) +
  scale_fill_manual(values=c("#FFFFFF", "#000000","#FFFFFF", "#000000"),
                    guide=FALSE) +
  theme_bw() +
  labs(list(x="", y='skeletal muscle FFA g/100g')) +
  # xlim("Baseline", "12w") +
  scale_x_discrete(expand = c(0,0)) + 
  scale_y_continuous(expand = c(0,0) ) + 
  theme(panel.border = element_blank(), panel.grid.major = element_blank(), 
        panel.grid.minor = element_blank(),
        axis.line = element_line(colour = "black"))

Which is pretty close to your example...