Subset time series based on their position

An mts object is reduced so as to contain only the first or last n timeseries. These functions work similarly to dplyr::slice_head and dplyr::slice_tail but apply to both dataframes in the mts object.

This is primarily useful when the mts object has been ordered by a previous call to mts_arrange or by some other means.

slice_head() selects the first and slice_tail() the last timeseries in the object.

mts_slice_head(mts, n = 5)

mts_slice_tail(mts, n = 5)

Arguments

mts

mts object.

n

Number of rows of mts$meta to select.

Value

A subset of the incoming mts time series object. (A list with meta and data dataframes.)

Examples

library(MazamaTimeSeries)

# Find lowest elevation sites
Camp_Fire %>%
  mts_filterMeta(!is.na(elevation)) %>%
  mts_arrange(elevation) %>%
  mts_slice_head(n = 5) %>%
  mts_extractMeta() %>%
  dplyr::select(elevation, locationName)
#> # A tibble: 5 × 2
#>   elevation locationName           
#>       <dbl> <chr>                  
#> 1      0.9  San Rafael             
#> 2      0.9  Redwood City           
#> 3      1.5  San Francisco          
#> 4      2.21 Calexico - Ethel Street
#> 5      2.7  Oakland West           

# Find highest elevation sites
Camp_Fire %>%
  mts_filterMeta(!is.na(elevation)) %>%
  mts_arrange(elevation) %>%
  mts_slice_tail(n = 5) %>%
  mts_extractMeta() %>%
  dplyr::select(elevation, locationName)
#> # A tibble: 5 × 2
#>   elevation locationName    
#>       <dbl> <chr>           
#> 1     1917. Tahoe City      
#> 2     2055. Lee Vining      
#> 3     2291  MMNPS1033       
#> 4     2306. Devil's Postpile
#> 5     2646. MMFS10401