Lattitude and longitude formats, an obvious observation

requiem said:
For mine, option-shift-8 gives the degree symbol: °, option-zero gives the similar but more obscure "ordinal indicator": º.
Click to expand...

I had never heard of ordinal indicators, so thanks for the link. I find that my suggestion (Character Map) knows about the two genders of ordinal indicator, too.

But the wiki article loses a little veracity by a misspelling, in an article on orthography: "... as practiced by scribes in monasteries..."!

Mike.

Mike.
 
So giving your location from GPS is not so simple

Maybe we should all put the app What3Words on our phones. It is very clever and gets away from this confusion

The website is https://what3words.com/

The introductory blurb has the following explanation

what3words is a really simple way to talk about location. We have divided the world into a grid of 3m x 3m squares and assigned each one a unique 3 word address. It means anyone can accurately find any location and share it more quickly, easily and with less ambiguity than any other system.

The service can be used via the free mobile app or online map. It can also be built into any other app, platform or website, with just a few lines of code.

For an example, her is the location of my boat

https://w3w.co/diet.ascribes.measurably

TudorSailor
 
tudorsailor said:
So giving your location from GPS is not so simple

Maybe we should all put the app What3Words on our phones. It is very clever and gets away from this confusion

The website is https://what3words.com/

The introductory blurb has the following explanation

what3words is a really simple way to talk about location. We have divided the world into a grid of 3m x 3m squares and assigned each one a unique 3 word address. It means anyone can accurately find any location and share it more quickly, easily and with less ambiguity than any other system.

The service can be used via the free mobile app or online map. It can also be built into any other app, platform or website, with just a few lines of code.

For an example, her is the location of my boat

https://w3w.co/diet.ascribes.measurably

TudorSailor
Click to expand...

What 3 words is great, however I don't see the problem with giving lat / long from the GPS ? If it's set to standard display which matches up to the charts... ie:

99° 99.999'

Then it's simple.
 
requiem said:
The first thing I do with any new navigational device or app is to set to MGRS if for land, and decimal minutes if for sea. What's really annoying is encountering modern charts that don't use decimal minutes.
Click to expand...

So now I had to google MGRS. It turns out to be Military Grid Reference System. Wikipaedia has this example

An example of an MGRS coordinate, or grid reference, would be 4QFJ12345678, which consists of three parts:

4Q (grid zone designator, GZD)
FJ (the 100,000-meter square identifier)
12345678 (numerical location; easting is 1234 and northing is 5678, in this case specifying a location with 10 m resolution)

Are you ex-military? Do you really set your devices to this format when on land?

TudorSailor
 
tudorsailor said:
So now I had to google MGRS. It turns out to be Military Grid Reference System. Wikipaedia has this example

An example of an MGRS coordinate, or grid reference, would be 4QFJ12345678, which consists of three parts:

4Q (grid zone designator, GZD)
FJ (the 100,000-meter square identifier)
12345678 (numerical location; easting is 1234 and northing is 5678, in this case specifying a location with 10 m resolution)

Are you ex-military? Do you really set your devices to this format when on land?

TudorSailor
Click to expand...

That reminds me of when I bought my first GPS back in 1997 and read the manual. It said (says, I have it here) "position format … UTM/UPS, British, German, Irish, Maidenhead, …". Since I live in Maidenhead, I initially thought that was a very astute bit of marketing! But it turns out "Maidenhead" is a grid especially for the ham radio community.

Mike.
 
tudorsailor said:
Are you ex-military? Do you really set your devices to this format when on land?
Click to expand...

No and yes; here’s what’s not immediately obvious about it:

1. It’s based on UTM, so is instantly compatible with any topo map having a UTM grid.
2. In the US, it’s equivalent to the US National Grid, which is the federal standard for georeferencing when, say, a hurricane or wildfire removes all the infrastructure.
3. It’s less unwieldy than UTM and can be truncated from both ends. Here’s an example:

On foot, you’re likely not traveling too far, meaning the zone and often the 100km square can be omitted. That means “4Q FJ 1234 5678” becomes “1234 5678” when there’s no risk of confusion. Also, 100 m is often sufficient precision, so you only need “123 567” in most cases. Finally, just as you can use minutes as a rough equivalent to nautical miles, these numbers represent actual meter distances on the ground.
 
I like the decimal minute notation.

First time I picked up the French equivalent of a OS Map UMT was a tad confusing for about 0.5 minute.
 
Frank Holden said:
Define 'recent'.... not in the last 55 years in my experience.

I do however have on the boat a French chart of Singapore Strait with minutes and seconds on it... chart is maybe 40 years old.
Click to expand...
I was taught this way about 35 years ago and was using charts marked this way until about 10 years ago, they were old charts with even older (1850) surveys on them. You would not have be allowed to use those charts on a commercial vessel. :)

Of course these new fangled cardinal buoys take a bit of getting used to :D :D
 
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