之前的推文介紹了一個鏈接巷懈，https://simplystatistics.org/2019/08/28/you-can-replicate-almost-any-plot-with-ggplot2/

這個里面有5個R語言ggplot2作圖的實例届腐，數(shù)據(jù)代碼都有仇冯，非常好的學(xué)習(xí)素材。但是他的代碼相對比較長，初學(xué)者看起來可能有些吃力。后面爭取出推文把代碼都拆解一下。今天的推文介紹一下其中的柱形圖實現(xiàn)的代碼

image.png

先介紹一個小知識點

ggplot2作圖X軸默認(rèn)坐標(biāo)軸的刻度是朝下的辟宗，Y軸默認(rèn)的刻度是朝左的，如果要改為朝上和朝右吝秕，該如何設(shè)置泊脐。之前也有人問過這個問題

library(ggplot2)
library(ggstar)

ggplot()+
  geom_star(aes(x=1,y=1),
            size=100,
            starshape=16,
            fill="red")+
  theme_bw()+
  theme(axis.ticks.length.x = unit(-1,'cm'),
        plot.margin = unit(c(1,1,2,1),'cm'),
        axis.text.x = element_text(vjust=-20),
        axis.title.x = element_text(vjust=-20),
        axis.ticks.length.y = unit(-1,'cm'),
        axis.text.y = 
          element_text(
            margin = margin(0,1.2,0,0,'cm')
          ))

image.png

這里我們把axis.ticks.length.x = unit(-1,'cm')刻度線的長度調(diào)整為負(fù)數(shù)就可以了，

但是還遇到一個問題是 橫坐標(biāo)的文本和標(biāo)題可以通過vjust參數(shù)上下調(diào)節(jié)烁峭，縱坐標(biāo)的參數(shù)卻不能夠用hjust的參數(shù)左右調(diào)節(jié)容客，不知道是什么原因

下面開始重復(fù)開頭提到的柱形圖

首先是數(shù)據(jù)，用到的是dslabs這個R包

安裝直接使用命令install.packages("dslabs")

加載數(shù)據(jù)集

library(dslabs)
data("nyc_regents_scores")

給數(shù)據(jù)集增加一列

library(dplyr)

nyc_regents_scores %>% head()

nyc_regents_scores$total <- rowSums(nyc_regents_scores[,-1], na.rm=TRUE)

對數(shù)據(jù)集過濾

如果score這一列是缺失值就把這行數(shù)據(jù)刪除

nyc_regents_scores %>% 
  filter(!is.na(score)) -> new_df

最基本的柱形圖

new_df %>%
  ggplot(aes(score, total)) + 
  geom_bar(stat = "identity", 
           color = "black", 
           fill = "#C4843C") 

image.png

指定位置添加背景

new_df %>%
  ggplot(aes(score, total)) + 
  annotate("rect", xmin = 65, 
           xmax = 99, 
           ymin = 0, 
           ymax = 35000, 
           alpha = .5) +
  geom_bar(stat = "identity", 
           color = "black", 
           fill = "#C4843C") 

image.png

添加文本注釋

new_df %>%
  ggplot(aes(score, total)) + 
  annotate("rect", xmin = 65, 
           xmax = 99, 
           ymin = 0, 
           ymax = 35000, 
           alpha = .5) +
  geom_bar(stat = "identity", 
           color = "black", 
           fill = "#C4843C") +
  annotate("text", 
           x = 66, 
           y = 28000, 
           label = "MINIMUM\nREGENTS DIPLOMA\nSCORE IS 65", 
           hjust = 0, 
           size = 3) +
  annotate("text",
           x = 0, 
           y = 12000, 
           label = "2010 Regents scores on\nthe five most common tests",
           hjust = 0, 
           size = 3)

image.png

修改坐標(biāo)軸刻度和位置

new_df %>%
  ggplot(aes(score, total)) + 
  annotate("rect", xmin = 65, 
           xmax = 99, 
           ymin = 0, 
           ymax = 35000, 
           alpha = .5) +
  geom_bar(stat = "identity", 
           color = "black", 
           fill = "#C4843C") +
  annotate("text", 
           x = 66, 
           y = 28000, 
           label = "MINIMUM\nREGENTS DIPLOMA\nSCORE IS 65", 
           hjust = 0, 
           size = 3) +
  annotate("text",
           x = 0, 
           y = 12000, 
           label = "2010 Regents scores on\nthe five most common tests",
           hjust = 0, 
           size = 3)+
  scale_x_continuous(breaks = seq(5, 95, 5), 
                     limit = c(0,99)) + 
  scale_y_continuous(position = "right") +
  ggtitle("Scraping By") + 
  xlab("") + ylab("Number of tests")

image.png

最后是對主題進(jìn)行設(shè)置

new_df %>%
  ggplot(aes(score, total)) + 
  annotate("rect", xmin = 65, 
           xmax = 99, 
           ymin = 0, 
           ymax = 35000, 
           alpha = .5) +
  geom_bar(stat = "identity", 
           color = "black", 
           fill = "#C4843C") +
  annotate("text", 
           x = 66, 
           y = 28000, 
           label = "MINIMUM\nREGENTS DIPLOMA\nSCORE IS 65", 
           hjust = 0, 
           size = 3) +
  annotate("text",
           x = 0, 
           y = 12000, 
           label = "2010 Regents scores on\nthe five most common tests",
           hjust = 0, 
           size = 3)+
  scale_x_continuous(breaks = seq(5, 95, 5), 
                     limit = c(0,99)) + 
  scale_y_continuous(position = "right") +
  ggtitle("Scraping By") + 
  xlab("") + 
  ylab("Number of tests")+
  theme_minimal() + 
  theme(panel.grid.major.x = element_blank(), 
        panel.grid.minor.x = element_blank(),
        axis.ticks.length = unit(-0.2, "cm"),
        plot.title = element_text(face = "bold"))

image.png

歡迎大家關(guān)注我的公眾號

小明的數(shù)據(jù)分析筆記本

小明的數(shù)據(jù)分析筆記本 公眾號 主要分享：1约郁、R語言和python做數(shù)據(jù)分析和數(shù)據(jù)可視化的簡單小例子缩挑；2、園藝植物相關(guān)轉(zhuǎn)錄組學(xué)鬓梅、基因組學(xué)供置、群體遺傳學(xué)文獻(xiàn)閱讀筆記；3绽快、生物信息學(xué)入門學(xué)習(xí)資料及自己的學(xué)習(xí)筆記芥丧！