User:Ekorren/Hash Inquiry Tool

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[edit] About

Small Hash Inquiry Tool is an online hashpoint calculator, just like many others. So why another one? Simply because I couldn't find one that did exactly what I wanted.

I wanted something that:

  • lists available nearby hashpoints, today and upcoming
  • may be called from a bookmark with saved default values
  • calculates approximate distance and direction
  • includes the globalhash
  • does it all at once, and
  • works on my outdated phone's crappy browser if I'm not at home

So, here it is.

And then I wanted something that:

  • shows all surrounding points at a glance on a map, also including the information from above

So, that one is now here as well.


[edit] Usage

Visit this link and enter your current coordinates and any options applying.

Coordinates are recognized in several common formats, among them D.d (-12.34567) and D M.m (12 34.567).

[edit] Options

  • Mode and number of points:
  • In list mode, the program calculates up to nine hashpoints per day, namely of the graticule where you are and the eight surrounding. It displays the nearest x of them. Set to zero if you only want to see the fractions and the globalhash.
  • In map overview mode, it shows you maps of the points in the surrounding graticules
  • Map link (only for list mode): If selected, a map link is added (no map, just the link).
  • Google dynamic: The standard variant of google maps, will work in most standard browsers but won't work on many mobile devices.
  • Google static: Static maps that should work virtually everywhere. The link will take you to a wrapper page where you can switch between different modes and scales.
  • Map size: If you choose static maps or map overview mode, you need to set the map size manually that it fits your screen. The dynamic map resizes itself and ignores this option.
  • Timezone: Leave blank to let the program guess based on your position (which is usually quite accurate), or set to your difference from UTC resp. UTC+1 during DST. This is only used to determine which day it is at your location so you will really get today's coordinates.
  • Date: If you really need retro coordinates (e.g. for the origin geohash), enter date in format yyyy-mm-dd. Leave blank for normal operation.
  • Distance unit: If you don't like kilometres, choose another one.

The resulting page can be bookmarked and directly called, as all data is included in the address line. You may even shorten the address line by removing all empty options.

[edit] More options in map overview

The map overview is always based on static google maps, the "map link" field is ignored. The size field is recognized, a recommendable width would be about 30% of your browser window width.

When on the map overview, you can among other options

  • switch between various zoom factors
  • switch between map modes
  • shift the displayed graticule set

Please notice that google maps limits the number of map requests from one IP within a certain timespan. One map overview page can generate up to 40 map requests, so your quota may be used up after only a small number of pages. If that happens to you, get yourself a cup of tea, and come back after a minute or so.

Each resulting page can be bookmarked and called directly from your browsers bookmarks without going through all selections again. It is encouraged to do this.

Using the map overview on an old mobile device isn't recommended (but might work somehow nonetheless).

[edit] Minimum mode

This is almost the shortest comprehensive hashpoint summary possible, usually about as long as this one sentence. It returns the available fractions in a short and easily parsable format but nothing else.

If you call the tool in this mode, note that you can strip the query string in the browser by all options except of nr=m (selecting minimum mode) and either lon=x or t=x (longitude resp. timezone - and in central europe you can even omit those two). As far as they make sense, other options are still recognized.

[edit] Issues

Well, theoretically there are a number of issues. None of them is really an issue in productive use, though.

No issue: This implementation is 30W and -0 compliant.

  • Distance to globalhash: Calculating distance and bearing gets inaccurate on long distances and very near to the poles, so if the program says that the globalhash is 8192 km in bearing 256°, you better shouldn't take this as a base for a ballistic flight as you probably will miss the spot. You can be sure that the distance is far too long to make it in time by bicycle, anyway.
  • Time zone issues: Time zones are only needed to determine which date it currently is at your place, so you neither get shown obsolete hashpoints nor miss valid ones. Autoguessing rarely fails by more than one or two hours, which means that the issue basically only turns up around midnight. If this bothers you, you'll need to set your timezone. And still may run into it because of varying daylight savings time.
  • There's a nearer one than #8 on the list! Well, this can happen. The program includes the own and the eight adjacent graticules. A point two graticules away may often be nearer than the farest in the surrounding graticules, but the nearest one to your location is one of those nine. Of course, there are rare exceptions to every rule. Bonus points if you find them. Double bonus points if you reach one. And don't forget about the MNIMB.
  • Unsupported locations: If your position is within of one degree from a pole, it will blow up your browser. This isn't as dangerous as it sounds because it only applies if the respective pole is a latitude 90 point but not if it's some pointy stick like thing or a person from Poland.

[edit] Maybe later

  • Formatted output (selectable).
  • Find a name that better suits the program since it isn't really small anymore.
  • Find a way to improve the server installation to get rid of some ridiculous workarounds.

[edit] Versions log

0.2.0 (2008-11-24): First release

0.2.2 (2008-12-01): Support for static map over wrapper page

0.2.3 (2008-12-02): Timezone support, including autoguessing

0.3.0 (2009-02-20): Map overview

0.3.2 (2009-03-03): If available, the name of the graticule the globalhash is in is given.

0.3.4 (2009-07-2x): shifting of map overview

0.3.5 (2009-07-27): switch to UTF-8, graticule links in map overview

0.4.0 (2009-08-05):

  • retro coordinates
  • ten different distance units to choose from for those not friends with kilometres.
  • input in more coordinate formats
  • list mode back to iso-8859-1, for lack of utf-8 compatibility in WAP browsers (map overview stays in utf-8)
  • bugfixes, new bugs (probably)

0.4.1 (2009-08-05): minimum mode