I am extracting a time variable from the output of an API request and the output format is as follows.
> a
[1] "2019-09-06T09:03:14.938Z"
The first objective is to derive the difference with Sys.time()
> b<- Sys.time()
> b
[1] "2019-09-06 08:57:08 UTC"
I am having issues to run a basic c = a-b
> c<-a-b
Error in `-.POSIXt`(a, b) : can only subtract from "POSIXt" objects
When trying to convert a into a POSIXT object, I get the following error:
> c<-as.POSIXct.Date(a)
Error in unclass(x) * 86400 : non-numeric argument to binary operator
The second objective would be to make the code wait until the time difference is possitive or zero. Maybe somethimg using sys.sleep?
You need to pass proper format while converting into POSIXct object
a <- as.POSIXct("2019-09-06T09:03:14.938Z", format = "%Y-%m-%dT%T")
and then do
b - a
You can also difftime which has units argument and can accept "secs", "mins", "hours","days", "weeks"
difftime(b, a, units = "mins")
Not exactly clear about the second part of the question however, we can write a while loop to make the code "wait" till time difference is positive or 0.
while(a > Sys.time()) { }