Fixing character lat/long columns in hypertibble() #128

[pvanlaake]

This PR fixes issue #128 where hyper_tibble() would produce character columns for latitude and longitude axes.

Description

In the previous modification of the method, use was made of dimnames(), which are indeed character labels. This has now been reverted to the original use of information from the transforms attribute of the tidync object.

Code

This is the new code for hyper_tibble() (with added <<< here):

hyper_tibble.tidync<- function(x, ..., na.rm = TRUE, force = FALSE) {
  
  slabs <- hyper_array(x, ...,  force = force)
  if (na.rm) all_na <- Reduce(`&`, lapply(slabs, 
                                          function(a) is.na(as.vector(a))))
  total_prod <- prod(dim(slabs[[1]]))
  out <- tibble::as_tibble(lapply(slabs, as.vector))
  
  prod_dims <- 1
  trans <- attr(slabs, "transforms")                <<< Access the transforms again

  for (i in seq_along(trans)) {
    nm <- names(trans)[i]
    nr <- sum(trans[[i]]$selected)
    
    out[[nm]] <- if ("timestamp" %in% colnames(trans[[i]]))   <<< Specific behaviour for CFtime timestamps
      rep(dplyr::filter(trans[[nm]], .data$selected)[["timestamp"]],
          each = prod_dims, length.out = total_prod)
    else
      rep(dplyr::filter(trans[[nm]], .data$selected)[[nm]],   <<< Original code, for other axes
          each = prod_dims, length.out = total_prod)

    prod_dims <- prod_dims * nr
  }
  if (na.rm) out <- dplyr::filter(out, !all_na)
 out
}

Resulting in:

> hyper_tibble(nc)
# A tibble: 9,034,094 × 4
   tempanomaly   lon   lat time      
         <dbl> <dbl> <dbl> <chr>     
 1       0.180  -179   -47 1880-01-15
 2       0.180  -177   -47 1880-01-15
 3       0.180  -175   -47 1880-01-15
 4      -0.110   171   -47 1880-01-15
 5      -0.110   173   -47 1880-01-15
 6      -0.110   175   -47 1880-01-15
 7       0.180  -179   -45 1880-01-15
...