/linz_tides

Primary LanguageLua

linz_tides

Predict tides at various places around New Zealand tide from LINZ tide data.

Instructions

  1. Decide on the prediction dates. I usually allow 1 day before and 2--3 days after the planned travel.
  2. Decide on the region that you will be travelling, and the primary and secondary ports in that region that you want predictions for.
  3. Create a 'trip', with a name that ties together the region you will be travelling in and the dates of the trip.
  4. Download tide tables for the primary ports involved over the dates of travel.
  5. Ensure that the secondary ports data is up-to-date.

How big will the database be

  • Number of ports: 250 (15 primary, 220 secondary)
  • Number of events: 1460 per year per port
  • Number of events per year: 365000

However, we only create secondary tide events when we create a trip, for the ports in the region where the trip occurs, and for the dates associated with the trip.

So the database is relatively small.

Features

  1. Read tide predictions for primary ports from a CSV file downloaded from LINZ -- DONE
  2. Adjust to NZDT when appropriate -- DONE
  3. Calculate tide time prediction for secondary ports -- DONE -- read data from LINZ data file..
  4. Calculate tide height predicition for secondary ports -- DONE
  5. Set up a number of different regions, with ports in that region -- DONE
  6. Set up a number of trips, with a region that the trip will take place, a start date and an end date -- DONE

TODO

  1. Find timezone library, rather than using my own.

  2. Choose port and time range to generate output for

  3. Format output for easy import into spreadsheet:

    Date        Nelson       Motueka      Astrolabe…   Sun      Moon
2013-12-27  0506 H 3.3   0511 H 3.3   0446 H 3.7            R 0129
Friday      1111 L 1.4   1130 L 1.5   1051 L 1.4            S 1458
            1744 H 3.4   1749 H 3.4   1724 H 3.8
            2353 L 1.2                2333 L 1.1

2013-12-28               0012 L 1.3                R 0554   R 0203
Saturday    0615 H 3.3   0620 H 3.3   0555 H 3.7   S 2102   S 1603
            1228 L 1.3   1247 L 1.4   1208 L 1.3
            1851 H 3.4   1856 H 3.4   1831 H 3.8

2013-12-29  0059 L 1.1   0118 L 1.2   0039 L 1.0            R 0243
Sunday      0729 H 3.5   0734 H 3.5   0709 H 3.9            S 1710
            1340 L 1.2   1359 L 1.3   1320 L 1.1
            1955 H 3.6   2000 H 3.6   1935 H 4.0

  4. Use a view for the secondary tide events rather than a table. Don't think this is possible, as we have to do a cartesian product of

    secondary_ports x primary_tide_events