From 8e1d9f44b2b2bc4031693855478f7201a7681053 Mon Sep 17 00:00:00 2001 From: Ben Burwell Date: Thu, 6 Feb 2020 15:04:34 -0500 Subject: improve docs --- README.md | 91 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 91 insertions(+) create mode 100644 README.md (limited to 'README.md') diff --git a/README.md b/README.md new file mode 100644 index 0000000..5a5a8e7 --- /dev/null +++ b/README.md @@ -0,0 +1,91 @@ +# `wx` - a command line interface for aviation weather + +`wx` fetches weather data from the NOAA Aviation Weather Center's Text Data +Server (TDS). + +## Installation from source + +1. Clone the repository +2. Run `sudo make install` + +## Usage + +Currently, we support fetching METARs in a variety of methods. When fetching +METARs, a time constraint must be supplied. A time constraint can either be in +the form "past x" or "between x and y". + + $ wx metar --past 3h + $ wx metar --since 2020-01-01T00:00:00 --until 2020-01-02T00:00:00 + +The `--past` argument defaults to `1h`, so if none of `--past`, `--since`, or +`--until` are specified, METARs from the past hour will be fetched. + +Note that the TDS only stores METARs from the past three days, so the `wx` +command cannot effectively be used to pull historical data. + +### For a set of stations + +You can fetch METARs from a set of stations by their full or partial ICAO IDs: + + $ wx metar kbos + $ wx metar kbos ksea + $ wx metar kb + +### For stations in a region + +You can fetch METARs from all stations within a rectangular or radial region. +Rectangular regions are specified by a `minLat,minLon,maxLat,maxLon` tuple: + + $ wx metar --rect 39,-70,40,-71 + +Radial regions are specified as a radius in statute miles around a center point +as a `dist,lat,lon` tuple: + + $ wx metar --radial 5.5,40,-70 + +### For stations along a flight path + +You can fetch weather for all stations with a distance of a specified flight +path. A flight path is specified by a series of `--waypoint` arguments, where +each waypoint can be an ICAO identifier or a `lon,lat` tuple. Waypoints must be +specified in order from origin to destination. + + $ wx metar --path-dist 10 --waypoint ksea --waypoint kbos + +### Controlling density + +When running a query which will return METARs from many stations, it may be +helpful to reduce the density of the results. This can be done with the +`--min-dist` argument which specifies a minimum distance (in degrees of latitude +or longitude) between stations to display. Providing a higher value for +`--min-dist` will result in fewer stations being returned. + + $ wx metar \ + --path-dist 10 --waypoint ksea --waypoint kbos \ + --min-dist 5 \ + +### Filtering recency + +There are two mechanisms for filtering results by recency. First, you can +request the single most recent METAR from all the stations being fetched: + + $ wx metar --past 6h kbos ksea --most-recent + +Even though we've specified two stations, KBOS and KSEA, we'll only get a single +METAR back from whichever of the two stations most recently made an observation. + +The second filtering mechanism is `--most-recent-by-station`. This argument can +take several values: + +* `constraint` (default): request the most recent for each METAR station in the + fastest fashion. +* `postfilter`: filter results after applying all other constraints. +* `false`: don't filter results to only the most recent for each station. + +## Contributing + +Email patches to . + +## License + +MIT -- cgit v1.2.3