monthlyIndices: Create Monthly Indices from NDVI3g Files

In gimms: Download and Process GIMMS NDVI3g Data

Create Monthly Indices from NDVI3g Files

Description

Create numeric monthly indices from (local or online) GIMMS NDVI3g filenames as input for the monthlyComposite function.

Usage

monthlyIndices(
  x,
  version = 1L,
  pos1 = ifelse(version == 1, 15L, 4L),
  pos2 = ifelse(version == 1, 23L, 8L),
  timestamp = FALSE,
  ...
)

Arguments

x	character. Vector of (local or online) filenames.
version	integer (or any other class convertible to integer). Specifies GIMMS NDVI3g product version, see 'Details' in updateInventory.
pos1, pos2	numeric. The first and last element of the date string in 'x', defaults to the GIMMS naming convention of the specified product version.
timestamp	logical, defaults to FALSE. If TRUE, an actual Date object is returned rather than a numeric vector of indices.
...	Currently not used.

Value

A numeric vector with unique monthly indices or, if timestamp = TRUE, the actual timestamps as Date objects.

See Also

monthlyComposite.

Examples

## NDVI3g.v1
gimms_files_v1 <- readRDS(system.file("extdata", "inventory_ecv1.rds", package = "gimms"))

monthlyIndices(gimms_files_v1[1], version = 1)                   # indices
monthlyIndices(gimms_files_v1[1], version = 1, timestamp = TRUE) # dates

## Similarly, NDVI3g.v0
gimms_files_v0 <- readRDS(system.file("extdata", "inventory_ecv0.rds", package = "gimms"))
gimms_files_v0 <- rearrangeFiles(gimms_files_v0) # reorder by date

monthlyIndices(gimms_files_v0[1:12], version = 0)
monthlyIndices(gimms_files_v0[1:12], version = 0, timestamp = TRUE)

gimms documentation built on Aug. 10, 2023, 1:07 a.m.