IDL - Struct of Arrays to Array of Structs

Question

From a FITS-Table I read data, and get a Struct containing the table, where each tag represents a column.

Is there a way to reformat the Struct of Arrays to an Array of Structs? So that one Struct in the Array represents a Row?

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General solution made by @mgalloy (see below):

function SoA2AoS, table

  if (table eq !NULL) then return, !NULL

  tnames = tag_names(table)
  new_table = create_struct(tnames[0], (table.(0)[0]))
  for t = 1L, n_tags(table) - 1L do begin
    new_table = create_struct(new_table, tnames[t], (table.(t))[0])
  endfor

  new_table = replicate(new_table, n_elements(table.(0)))

  for t = 0L, n_tags(table) - 1L do begin
    new_table.(t) = table.(t)
  endfor

  return, new_table

end

Answer 1

You can do it without knowing the names of the tags too (untested code):

; suppose table is a structure containing arrays
tnames = tag_names(table)
new_table = create_struct(tnames[0], (table.(0))[0]
for t = 1L, n_tags(table) - 1L do begin
  new_table = create_struct(new_table, tnames[t], (table.(t))[0])
endfor
table = replicate(table, n_elements(table.(0)))
for t = 0L, n_tags(table) - 1L do begin
  new_table.(t) = table.(t)
endfor