as.POSIXlt.character中的Dygraphs错误

Question

尝试使用dygraphs包创建图。我已经转换使用as.Date（日期），但我得到这个消息：

Error in as.POSIXlt.character(x, tz, ...) : 
    character string is not in a standard unambiguous format 

我的第一数据的几行看起来是这样的：

  Date Depth  Fecal.Coliform Dissolved.Oxygen 
1 1992-05-02 0.5   6.0    NA 
2 1992-05-15 0.5    NA   9.900000 
3 1992-05-31 0.5    NA   8.800000 
4 1992-06-11 0.5    NA   8.900000 

Answer 1

看来dygraphs喜欢时间序列数据超过日期。尝试使用xts到您的日期转换：

library(xts) 
library(dygraphs) 

data <- data.frame(Date = as.Date(c("1992-05-02", "1992-05-15", 
            "1992-05-31", "1992-06-11")), 
        Depth = c(0.5, 0.5, 0.5, 0.5), 
      Fecal.Coliform = c(6.0, NA, NA, NA), 
     Dissolved.Oxygen = c(NA, 9.900000, 8.800000, 8.900000)) 

# This produces your error 
dygraph(data) 

# convert your data to time series and plot it! 
new.data <- cbind(xts(data$Dissolved.Oxygen, data$Date), 
         data$Fecal.Coliform, data$Depth) 
colnames(new.data) <- c("Dissolved.Oxigen", "Fecal.Coliform", "Depth") 
dygraph(new.data)