全年年度时间序列的R热图

Question

我正在尝试制作一张R河口几年来盐度日平均值的热图。

我希望格式包括在x轴上的月份和y轴上的年，所以每年1月1日直接在另一个1月1日。换句话说，不像典型的年历风格(不像这样：http://www.r-bloggers.com/ggplot2-time-series-heatmaps/)。

到目前为止，我只能在一年中的某一天使用以下命令进行绘图：

{r} d <- read.xlsx('GC salinity transposed.xlsx', sheetName = "vert-3", header = TRUE, stringsAsFactors = FALSE, colClasses = c("integer", "integer", "numeric"), endRow = 2254)

{r} ggplot(d, aes(x = Day.Number, y = Year)) + geom_tile(aes(fill = Salinity)) + scale_fill_gradient(name = 'Mean Daily Salinity', low = 'white', high = 'blue') + theme(axis.title.y = element_blank())

并获得这个：heat map not quite right

有没有人能告诉我一个更好的方法--在x轴上包含月份，而不是一年中的某一天？谢谢。R的新手。

Answer 1

对于这样的东西，lubridate包很方便。这段代码能做你想要的吗？我假设你每个月只有一次盐度读数，并且不需要在同一个月中对多个值进行平均。

library(lubridate)
library(ggplot2)

# Define some data
df <- data.frame(date = seq.Date(from = as.Date("2015-01-01"), by = 1, length.out = 400),
                 salinity = runif(400, min=5, max=7))
# Create fields for plotting
df$day <- paste0(ifelse(month(df$date)<10,"0",""),
                 month(df$date),
                 "-",
                 ifelse(day(df$date)<10,"0",""),
                 day(df$date))
df$month <- paste0(ifelse(month(df$date)<10,"0",""),
                   month(df$date))
df$year <- year(df$date)
library(lubridate)
library(ggplot2)

# Define some data
df <- data.frame(date = seq.Date(from = as.Date("2015-01-01"), by = 1, length.out = 400),
                 salinity = runif(400, min=5, max=7))
# Create fields for plotting
df$day <- paste0(ifelse(month(df$date)<10,"0",""),
                 month(df$date),
                 "-",
                 ifelse(day(df$date)<10,"0",""),
                 day(df$date))
df$month <- paste0(ifelse(month(df$date)<10,"0",""),
                   month(df$date))
df$year <- year(df$date)
#Plot results by month
ggplot(data=df) +
  geom_tile(aes(x = month, y = year, fill = salinity)) +
  scale_y_continuous(breaks = c(2015,2016))
#Plot results by day
ggplot(data=df) +
  geom_tile(aes(x = day, y = year, fill = salinity)) +
  scale_y_continuous(breaks = c(2015,2016))

每个月的结果：

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一天一次的结果(你真的想这样吗？366个x轴值很难读懂)：

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