Remove the space between the bars in the grid

Question

I want to move bars that are within the same grid closer to save space. Is there a way to do this? The code I used just changes the width of the strip and does not change the interval. I know that bindwidth no longer works in geom_bar since I mentioned these problems:

Adding space between bars in ggplot2 Increase the space between bars in ggplot

This is data

 dput(grp1) structure(list(Rot = structure(c(1L, 1L, 1L, 1L, 2L, 2L, 2L, 2L, 2L, 2L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L), .Label = c("2-year", "3-year", "4-year"), class = "factor"), Rot.Herb = structure(c(3L, 4L, 13L, 14L, 5L, 6L, 9L, 10L, 15L, 16L, 1L, 2L, 7L, 8L, 11L, 12L, 17L, 18L), .Label = c("A4-conv", "A4-low", "C2-conv", "C2-low", "C3-conv", "C3-low", "C4-conv", "C4-low", "O3-conv", "O3-low", "O4-conv", "O4-low", "S2-conv", "S2-low", "S3-conv", "S3-low", "S4-conv", "S4-low"), class = "factor"), Rot.trt = structure(c(2L, 2L, 7L, 7L, 3L, 3L, 5L, 5L, 8L, 8L, 1L, 1L, 4L, 4L, 6L, 6L, 9L, 9L), .Label = c("A4", "C2", "C3", "C4", "O3", "O4", "S2", "S3", "S4"), class = "factor"), Crop = structure(c(2L, 2L, 4L, 4L, 2L, 2L, 3L, 3L, 4L, 4L, 1L, 1L, 2L, 2L, 3L, 3L, 4L, 4L), .Label = c("alfalfa", "corn", "oat", "soybean"), class = "factor"), Year = c(2014L, 2014L, 2014L, 2014L, 2014L, 2014L, 2014L, 2014L, 2014L, 2014L, 2014L, 2014L, 2014L, 2014L, 2014L, 2014L, 2014L, 2014L), Herb.trt = structure(c(1L, 2L, 1L, 2L, 1L, 2L, 1L, 2L, 1L, 2L, 1L, 2L, 1L, 2L, 1L, 2L, 1L, 2L), .Label = c("conv", "low"), class = "factor"), variable = structure(c(1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L), .Label = "kg.ha", class = "factor"), N = c(4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4), value = c(0.43168573275, 16.22463846275, 0.554446363, 25.89844593075, 13.882743364, 84.1922080725, 84.2625, 105.7375, 0.8350420895, 106.7464386085, 127.8875, 65.3875, 1.964170084, 29.46524929925, 249.7625, 333.125, 0.535560112, 28.757014893), sd = c(0.528135488290589, 20.3216237207314, 0.8810357408252, 40.4576156325903, 27.3195114207629, 71.6424882235524, 22.6948736869511, 40.9587266851237, 0.931926987921512, 108.45555847826, 89.1035387905553, 25.141843442092, 2.20017281317418, 24.1072626208021, 93.2983509589889, 85.0439543216722, 0.48339034731648, 33.2628789566726), se = c(0.264067744145294, 10.1608118603657, 0.4405178704126, 20.2288078162951, 13.6597557103815, 35.8212441117762, 11.3474368434756, 20.4793633425619, 0.465963493960756, 54.2277792391299, 44.5517693952777, 12.570921721046, 1.10008640658709, 12.0536313104011, 46.6491754794945, 42.5219771608361, 0.24169517365824, 16.6314394783363), ci = c(0.840381416699796, 32.3362381637038, 1.40192446910603, 64.3770946952626, 43.4714390915815, 113.999185974188, 36.112608456959, 65.1744742040986, 1.48290379975249, 172.576995683309, 141.783613905853, 40.0062833851536, 3.50096592013592, 38.3600344290379, 148.458496149248, 135.323909108861, 0.76918191241357, 52.928663119381 )), .Names = c("Rot", "Rot.Herb", "Rot.trt", "Crop", "Year", "Herb.trt", "variable", "N", "value", "sd", "se", "ci"), row.names = c(NA, -18L), class = "data.frame") 

This is the code

 ggplot(grp1, aes(x=Rot.Herb, y=value, fill=factor(Herb.trt)))+ geom_bar(stat="identity", position=position_dodge(.), width=.5)+ scale_fill_brewer(palette = "Dark2")+ theme_bw() + theme(panel.grid.major=element_blank()) + facet_grid(~Crop, scales = "free_x", space="free_x")+ theme(legend.title=element_blank(),legend.text=element_text(size=20),legend.position="top")+ geom_errorbar(aes(ymin=value-se, ymax=value+se), size=0.75, width=.25,position=position_dodge(.5))+ xlab("Treatment") + theme(axis.title = element_text(size=24,face="bold", vjust=4)) + ylab("2014 total weed biomass (Kg/ha)\n") + theme(axis.title = element_text(size=24,face="bold", vjust=2), axis.text.y = element_text(size=20, color="black"))+ theme(strip.text.x = element_text(colour = "black", size = 15), strip.background = element_rect(fill = "white"), axis.text.x = element_blank(), axis.ticks.x = element_blank()) 

And the schedule

What I want is a graph with a bar width of 0.5 and no gaps between columns in the same grid. Thanks for all the input.

Answer 1

I think you want width = 0.5 while keeping the bars touching, because you don't want the absolute width to change ( width = 0.5 changes the relative width). It may be closer to what you are asking.

 ggplot(grp1, aes(x=Rot.Herb, y=value, fill=factor(Herb.trt)))+ geom_bar(stat="identity", position = "dodge", width=1)+ scale_x_discrete(expand=c(0.2,0))+ scale_fill_brewer(palette = "Dark2")+ theme_bw() + theme(panel.grid.major=element_blank()) + facet_grid(~Crop, scales = "free_x", space="free_x")+ theme(legend.title=element_blank(),legend.text=element_text(size=20),legend.position="top")+ geom_errorbar(aes(ymin=value-se, ymax=value+se), size=0.75, width=.25,position=position_dodge(0.5))+ xlab("Treatment") + theme(axis.title = element_text(size=24,face="bold", vjust=4)) + ylab("2014 total weed biomass (Kg/ha)\n") + theme(axis.title = element_text(size=24,face="bold", vjust=2), axis.text.y = element_text(size=20, color="black"))+ theme(strip.text.x = element_text(colour = "black", size = 15), strip.background = element_rect(fill = "white"), axis.text.x = element_blank(), axis.ticks.x = element_blank()) 

Basically, I changed width = 1 , as suggested by @Gregor, which leads to touch strokes, but added an additional option scale_x_discrete(expand=c(0.2,0)) to add spaces between the stripes and the sides of the chart. This actually adjusts the absolute width of the rods while maintaining their touch. The first number gives the multiplicative constant used to expand the range, and the second gives the additive.

You can experiment with two values ​​in expand = to get what you want.

Also see this related question: ggplot geom_boxplot: narrowing the gap between x-axis categories