R 可视化

R-ggChernoff包绘制表情符号

R-ggChernoff包作为ggplot2的拓展包，其提供的geom_chernoff()绘图函数与geom_point()函数语法类似，只不过，其绘制的为带笑脸的表情符号，而不是常规的点。这种笑脸表情符号制作过程依据如下：脸部特征会根据连续值的相对大小变换成微笑或者皱眉。默认情况下，平均值将生成笔直的脸😑，而较高的值将产生笑脸😊，而较低的值将产生皱眉😢。如果没有映射到相应变量，默认将全部都是笑脸。更多详细内容可参考R-ggChernoff包官网
接下来，将通过几个例子进行该包的解释：

「样例一」：

  1. library(ggChernoff)
  2. library(tidyverse)
  3. library(ggtext)
  4. library(hrbrthemes)
  5. library(LaCroixColoR)
  7. geom_chernoff_plot01 <- ggplot() +
  8.   geom_chernoff(data = iris,aes(Petal.Width, Petal.Length, fill = Species),
  9.                size=5) +
  10.    scale_fill_manual(values = lacroix_palette(type = "paired"))+
  11.    labs(
  12.     title = "Example of <span style='color:#D20F26'>ggChernoff::geom_chernoff function</span>",
  13.     subtitle = "processed charts with <span style='color:#1A73E8'>geom_chernoff()</span>",
  14.     caption = "Visualization by <span style='color:#0057FF'>DataCharm</span>") +
  15.   hrbrthemes::theme_ipsum(base_family = "Roboto Condensed") +
  16.   theme(
  17.     plot.title = element_markdown(hjust = 0.5,vjust = .5,color = "black",
  18.                                   size = 20, margin = margin(t = 1, b = 12)),
  19.     plot.subtitle = element_markdown(hjust = 0,vjust = .5,size=15),
  20.     plot.caption = element_markdown(face = 'bold',size = 12))

绘图技巧 | 绘制“符号”可视化图表 - 图1
Example01 of ggChernoff

「样例二」：

  1. test_data <- lattice::barley %>% filter(site==c("University Farm","Waseca","Morris"))
  2. geom_chernoff_plot02 <- ggplot() +
  3.   geom_chernoff(data=test_data,aes(x = year, y = variety, smile = yield, brow = yield),
  4.                 fill = 'goldenrod1',size=8) +
  5.   scale_x_discrete(limits = c('1931', '1932')) +
  6.   #分面处理
  7.   facet_wrap(~ site) +
  8.   labs(
  9.     title = "Example of <span style='color:#D20F26'>ggChernoff::geom_chernoff function</span>",
  10.     subtitle = "processed charts with <span style='color:#1A73E8'>geom_chernoff()</span>",
  11.     caption = "Visualization by <span style='color:#0057FF'>DataCharm</span>") +
  12.   hrbrthemes::theme_ipsum(base_family = "Roboto Condensed") +
  13.   theme(
  14.     plot.title = element_markdown(hjust = 0.5,vjust = .5,color = "black",
  15.                                   size = 20, margin = margin(t = 1, b = 12)),
  16.     plot.subtitle = element_markdown(hjust = 0,vjust = .5,size=15),
  17.     plot.caption = element_markdown(face = 'bold',size = 12))

绘图技巧 | 绘制“符号”可视化图表 - 图2
Example02 of ggChernoff
以上两个例子很好的解释了geom_chernoff() 绘图函数的绘图原理(其实就是将数值映射到smile、brow等参数上)，大家可根据自己的数据进行合理的数值映射即可。接下来，小编再介绍另一个绘制符号字体的R包。

R-emojifont包绘制表情符号

R-emojifont包不同于上面介绍的R包，其支持的符号字体(emoji font)也更加丰富，主要包括：Emoji characters(表情符号字符) 和 Font Awesome。更多信息可参考R-emojifont包官网
接下来，通过几个例子进行简单描述：

「样例一」：

  1. data <- data.frame(
  2.   name=c("A","B","C","D","E") ,  
  3.   value=c(3,10,19,28,45),
  4.   label = c(emoji('smiley'), emoji('smile'),emoji('sweat_smile'), 
  5.             emoji('smiley_cat'),emoji('smirk'))
  6. )
  8. Barplot <- ggplot(data, aes(x=name, y=value,label=label,fill=name)) + 
  9.   geom_bar(stat = "identity",color="black",width = .8) +
  10.   geom_text(aes(y=value+6,color=name),family="EmojiOne", 
  11.             size=8) +
  12.   hrbrthemes::scale_color_ipsum()+
  13.   hrbrthemes::scale_fill_ipsum()+
  14.   labs(
  15.     title = "Example of <span style='color:#D20F26'>emojifont::EmojiOne</span>",
  16.     subtitle = "processed charts with <span style='color:#1A73E8'>EmojiOne</span>",
  17.     caption = "Visualization by <span style='color:#0057FF'>DataCharm</span>") +
  18.   hrbrthemes::theme_ipsum(base_family = "Roboto Condensed")+
  19.   theme(plot.title = element_markdown(hjust = 0.5,vjust = .5,color = "black",
  20.                                       size = 20, margin = margin(t = 1, b = 12)),
  21.         plot.subtitle = element_markdown(hjust = 0,vjust = .5,size=15),
  22.         plot.caption = element_markdown(face = 'bold',size = 12))

绘图技巧 | 绘制“符号”可视化图表 - 图3
Example01 of emojifont
这里可以看出，在每个柱形图的上方添加了对于的表情符合，当然，还可以单独使用表情符号进行绘制：

「样例二」：

  1. ##plot2
  2. x = seq(0, 2*pi, length=30)
  3. y = sin(x)
  4. ggplot() + geom_emoji('heartbeat', x=x, y=y, 
  5.                       size=10,color = "red") +
  6.   labs(
  7.     title = "Example of <span style='color:#D20F26'>emojifont::geom_emoji</span>",
  8.     subtitle = "processed charts with <span style='color:#1A73E8'>geom_emoji()</span>",
  9.     caption = "Visualization by <span style='color:#0057FF'>DataCharm</span>") +
  10.   hrbrthemes::theme_ipsum(base_family = "Roboto Condensed")+
  11.   #theme_ft_rc(base_family = "Roboto Condensed") +
  12.   theme(plot.title = element_markdown(hjust = 0.5,vjust = .5,color = "black",
  13.                                       size = 20, margin = margin(t = 1, b = 12)),
  14.         plot.subtitle = element_markdown(hjust = 0,vjust = .5,size=15),
  15.         plot.caption = element_markdown(face = 'bold',size = 12),
  16.         # 去除刻度线和网格线
  17.         axis.text.x = element_blank(),
  18.         axis.text.y = element_blank(),
  19.         axis.title.x = element_blank(),
  20.         axis.title.y = element_blank(),
  21.         panel.grid.major = element_blank(),
  22.         panel.grid.minor = element_blank())

绘图技巧 | 绘制“符号”可视化图表 - 图4
Example of geom_emoji()

「样例三」：

  1. df<-read_excel("test_data.xlsx")
  3. ##数据处理
  4. df <- df %>% mutate(
  5.   emoji_label = if_else(gender == "Male",fontawesome("fa-mars-double"),
  6.                         fontawesome("fa-venus-double")))
  8. example <- ggplot(data = df,aes(decade, category, color = as.numeric(prop), label = emoji_label)) +
  9.   geom_tile(fill = "grey25", color = "grey20", size = 1) +
  10.   geom_text(family = 'fontawesome-webfont', size = 6) +
  11.   facet_grid(. ~ gender) +
  12.   scale_color_scico(palette = "buda", name = NULL, na.value = "grey25",
  13.                     guide = guide_colorbar(direction = "horizontal",
  14.                                            barheight = unit(3, units = "mm"), 
  15.                                            barwidth = unit(150, units = "mm"),
  16.                                            draw.ulim = FALSE, title.position = 'bottom',
  17.                                            title.hjust = 0.5, label.hjust = 0.5)) +
  18.   labs(
  19.     title = "Example of emojifont library",
  20.     subtitle = "processed charts with geom_text()")+
  21.   theme(
  22.     strip.text = element_blank(),
  23.     rect = element_rect(fill = "grey20", colour = "grey20", size = 0.4, 
  24.                         color = "grey20",linetype = 1),
  25.     plot.background = element_rect(color = "grey20"),
  26.     panel.background = element_rect(fill = NA, colour = NA), 
  27.     panel.border = element_rect(colour = "grey85", fill = NA, color = "grey20",size = rel(1)),
  28.     panel.grid = element_blank(),
  29.     plot.title = element_text(size = 15, hjust = 0.5, vjust = 1, face = "bold",colour = "white"),
  30.     plot.subtitle = element_text(size = 12, hjust = 0.5, vjust = 1,colour = "white"),
  31.     axis.text = element_text(size = 9,colour = "grey85"),
  32.     legend.position = "bottom",
  33.     legend.text = element_text(colour = "white"),
  34.     axis.ticks = element_blank(),
  35.     axis.title = element_blank()
  36.     axis.text = element_text(size=10))

绘图技巧 | 绘制“符号”可视化图表 - 图5
Example03 of emojifont