How can I convert Float data type to location in Looker

[analyst2205]

In view file I am extracting some dimensions from another view file/table which has Float as their data type. I want to convert all these dimensions data type into location after extracting. How I can do this in view file?

Please check my code:

view: trip_summary_maps {
  derived_table: {
    sql: SELECT
    destination_trip_summary.start_lat  AS destination_trip_summary_start_lat,
    destination_trip_summary.start_lng  AS destination_trip_summary_start_lng,
    destination_trip_summary.end_lat  AS destination_trip_summary_end_lat,
    destination_trip_summary.end_lng  AS destination_trip_summary_end_lng
FROM `mydataset.destination_trip_summary`;;
}
  dimension: end_lat {
    type: location
    sql: sql: CAST(${TABLE}.string_field as LOCATION);;
  }