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I’m trying to create a script that shows the sunrise and sunset with the latitudes set, but the time is not compatible. OBS: this latitude corresponds to the time of São Paulo.
library(maptools)
library(dplyr)
dateInt <- c("2017-10-11","2017-10-01")
lon <- -46.6821862
lat <- -23.5977319
timezone <- 'UTC+3'
date <- dateInt[2]
if (length(dateInt)==1) {
span <- 1
}else {
span <- difftime(strptime(dateInt[1], format = "%Y-%m-%d")
,strptime(dateInt[2], format = "%Y-%m-%d"),units="days")
span <- as.numeric(span)
span <- span
}
lon.lat <- matrix(c(lon, lat), nrow=1)
day <- as.POSIXct(date, tz=timezone)
sequence <- seq(from=day, length.out=span , by="days")
#Getting datas
sunrise <- sunriset(lon.lat, sequence, direction="sunrise", POSIXct.out=TRUE)
sunset <- sunriset(lon.lat, sequence, direction="sunset", POSIXct.out=TRUE)
solar_noon <- solarnoon(lon.lat, sequence, POSIXct.out=TRUE)
day_length <- round(as.numeric(sunset$time-sunrise$time),2)
r <- data.frame(Data=as.Date(sunrise$time),
Nascer=format(sunrise$time, "%H:%M"),
`Meio Dia`=format(solar_noon$time, "%H:%M"),
Pôr=format(sunset$time, "%H:%M"),
`Duração(Horas)` = day_length)
#sorting dataframe by Data
r <- r[order(r, decreasing = TRUE),]
r <- data.frame(lapply(r, as.character), stringsAsFactors=FALSE)
#Removing N/A
r <- na.omit(r)
r
Why is the schedule not compatible? What time should appear?
– Tomás Barcellos
Sp is UTC -3, but for the time to be really similar, I have to put UTC+3, even so, there is the delay around 30 minutes.
– Juny