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library(tidyverse)
library(reprex)
setwd("C:/Users/Moritz Röttgen/Desktop/reprex")
#Datensätze einlesen ----
Loeffler <- read_delim("Loeffler_Gesamt1.CSV",";", escape_double = FALSE, trim_ws = TRUE)%>% #Unbearbeitete Tabelle einladen
gather(key = Kategorie, value = Anzahl, -Kolonie, -Nestnummer,-Nestteil, -Art, -Probe) #Den Datensatz Tidy machen
#> Warning: Duplicated column names deduplicated: 'Fischkisten' =>
#> 'Fischkisten_1' [86], 'Hummerreusen' => 'Hummerreusen_1' [102]
#> Parsed with column specification:
#> cols(
#> .default = col_double(),
#> Art = col_character(),
#> Kolonie = col_character(),
#> Nestteil = col_character()
#> )
#> See spec(...) for full column specifications.
kormoran <- read_delim("Kormoran_Gesamt1.CSV", ";", escape_double = FALSE, trim_ws = TRUE)%>% #Unbearbeitete Tabelle einladen
gather(key = Kategorie, value = Anzahl, -Nestnummer,-Nestteil, -Art) #Den Datensatz Tidy machen
#> Warning: Duplicated column names deduplicated: 'Fischkisten' =>
#> 'Fischkisten_1' [84], 'Hummerreusen' => 'Hummerreusen_1' [100]
#> Parsed with column specification:
#> cols(
#> .default = col_double(),
#> Art = col_character(),
#> Nestteil = col_character()
#> )
#> See spec(...) for full column specifications.
#Tabellen zusammenfügen ----
Gesamt <- bind_rows(Loeffler, kormoran, .id = NULL)
#Gesamtzahlen vergleichen ----
Vergleich <- Gesamt %>%
group_by(Art, Nestteil, Nestnummer)%>%
summarise(Anzahl = sum(Anzahl))%>%
ungroup(Nestnummer)%>%
group_by(Art, Nestteil)%>%
mutate( Stab = sd(Anzahl), count = n(), se = (Stab/(sqrt(count))))%>%
group_by(Stab, count, se, add=T)%>%
summarise(Gesamt = sum(Anzahl))
Vergleich
#> # A tibble: 8 x 6
#> # Groups: Art, Nestteil, Stab, count [8]
#> Art Nestteil Stab count se Gesamt
#> <chr> <chr> <dbl> <int> <dbl> <dbl>
#> 1 Kormoran Kein 0.601 9 0.200 8
#> 2 Kormoran Mitte 3.19 30 0.583 75
#> 3 Kormoran Oben 1.16 30 0.212 31
#> 4 Kormoran Unten 0.837 30 0.153 9
#> 5 Loeffler Kein 6.63 9 2.21 51
#> 6 Loeffler Mitte 37.6 29 6.98 617
#> 7 Loeffler Oben 6.64 29 1.23 204
#> 8 Loeffler Unten 2.47 29 0.459 42
plot_vergleich <- ggplot(Vergleich, aes(x = Nestteil, y = Gesamt, fill = Nestteil))+
geom_bar(stat = 'identity', position = 'dodge')+
geom_errorbar(aes( ymin = Gesamt - se, ymax = Gesamt + se ), width = .4)+
geom_text(aes(label = Gesamt), size = 5, position = position_dodge(0.8), vjust = -0.9)+
geom_text(aes(x=3.3, y = 65), label = 'n = 123', size = 6)+
geom_text(x=3.3, y =535, label = 'n = 914', size = 6)+
scale_fill_brewer(name= 'Nestteil', palette = 'Greys')+
labs(x ='', y = expression('Gesamtnanzahl der gefundenen Müllteile'))+
facet_wrap(~Art, scales = 'free')+
theme(panel.background = element_rect(fill = NA),
panel.grid.major.y = element_line(color='grey', linetype = 20, size = 0.5),
axis.line.x = element_line(linetype = 'solid'),
axis.line.y = element_line(linetype = 'solid'),
strip.background = element_blank(),
strip.text = element_text(size = 12, face = 'bold'),
axis.text.x = element_text(size = 19, family = 'sans', colour = 'black'),
axis.title.y = element_text(size = 19, family = 'sans', colour = 'black'),
legend.text = element_text(size = 19,family = 'sans', colour = 'black'),
legend.title = element_text(size = 19,family = 'sans', colour = 'black'))
plot_vergleich

Created on 2019-06-20 by the reprex package (v0.3.0)
The colum "Art" specifys the facet_wrap, the colum "Nestteil" is my x and the colum "Gesamt" is my y.
Now I want the sum of the colum "Gesamt" per species (colum "Art" these are two different species of birds) as a geom_text like "n = 123". The problem stays the same, the "n = 123" should just appear left. Hope you can understand my request better now. Thank you very much effort helping me out!