as.yearmon2: Conditionally convert x to yearmon if the conversion is...
In FinTS: Companion to Tsay (2005) Analysis of Financial Time Series

Description Usage Arguments Details Value See Also Examples

Convert x to class "yearmon". If duplicate months are found, return x. Otherwise, return the conversion with names = x.

1	as.yearmon2(x, ...)

`x`	object suitable for `as.yearmon`
`...`	additional argument(s) (e.g., a format) passed to `as.yearmon`.

Dates for some monthly data include the day of the month on which the data were published. For many purposes, one would like to have the data as a zoo object with a yearmon index, while still retaining the full date for other purposes.

If the yearmon form of the input is not uniqe, as.yearmon2 returns the input unchanged with a warning. Otherwise, it returns the yearmon conversion with the input as names.

Returns either its argument or its argument converted to class yearmon with names.

yearmon

x1 <- as.Date(c("2000-01-01", "2000-01-01"))
as.yearmon2(x1)
#Warning message:
#In as.yearmon2(x1) :
#  1 duplicate months found in 'x';  returning 'x' unchanged

x2 <- as.Date(c("2000-01-01", "2000-02-01"))
as.yearmon2(x2)
# month of x2 with names x2