Method: Ephem::Excerpt::DAFWriter#setup_formats

Defined in:
lib/ephem/excerpt.rb

#setup_formats(nd, ni) ⇒ Object 



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# File 'lib/ephem/excerpt.rb', line 253

def setup_formats(nd, ni)
  @nd = nd
  @ni = ni

  # Double is always 8 bytes, int is always 4 bytes
  double_size = 8
  int_size = 4

  # Set formats based on endianness
  if @endianness == :little
    @double_format = "E"  # Little-endian double
    @int_format = "l"     # Little-endian signed long (32-bit)
  else
    @double_format = "G"  # Big-endian double
    @int_format = "l>"    # Big-endian signed long (32-bit)
  end

  # Create formats for summary structures
  @summary_control_format =
    "#{@double_format}#{@double_format}#{@double_format}"
  @summary_format = @double_format.to_s * @nd + @int_format.to_s * @ni

  # Calculate segment summary sizes
  @summary_length = double_size * @nd + int_size * @ni

  # Pad to 8 bytes
  @summary_step = @summary_length + (-@summary_length % 8)

  @summaries_per_record = (RECORD_SIZE - 8 * 3) / @summary_step
end