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Flatiron
08-25-2005, 05:08 AM
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Bob
08-25-2005, 07:19 AM
Sorry, Donít know the program but I wrote such a thing dozen years ago for my own database. I took lat/long coordinates in decimal degrees from the over 3,000 ghost towns locations Iíve collected in Nevada and then plug in a location (like a motel in Fallon) and it will spit out every location within an arbitrary distance. Just wrote it one evening as a console applications, it reads the data one line at a time from a text file (Passed as a command line argument) and outputs to the screen, which I then redirect to a file. Probably could find it and post the code. if your program is too expensive. Made some assumptions like the earth is flat so only works for a area the size of a UTM but if distances are less than 600 miles that should not be a factor. You know a degree longitude gets shorter as you go further north so I used the distance at the center point (place I plugged in like the motel in Fallon) and didnít bother with the curvature of the earth or the lumpinessí (The earth, kinda like this old man, bulges at the middle) but for line of sight distances within a couple hundred miles these factors are inconsequential. If you use UTM you make the same assumptions. Simple geometry and a little trig if you call Pythagoras' Theorem Trig. :)

Dezdan
08-25-2005, 01:57 PM
I have a program that I installed that allows one to move the cursor to any point on chosen maps to get the coordinates. It also gives you the distance (as a crow flies) from one waypoint to another, as well as highlighting it on the map for printing...but maybe somebody else on the site may know of the program.Was your post meant to be a reply to another message FaltIron? Anyway, I can think of a few programs that will doing such a thing FlatIron, perhaps one of them will jog your memory:

National Geographic TOPO!:
http://maps.nationalgeographic.com/topo/ (http://maps.nationalgeographic.com/topo/)

DeLorme Topo USA:
http://www.delorme.com/topousa/default.asp (http://www.delorme.com/topousa/default.asp)

DeLorme 3-D TopoQuads:
http://www.delorme.com/quads/default.asp (http://www.delorme.com/quads/default.asp)

Maptech Terrain Navigator/Pro:
http://www.maptech.com/land/terrainnavigator/index.cfm (http://www.maptech.com/land/terrainnavigator/index.cfm)

Garmin MapSource Topo US:
http://www.garmin.com/cartography/mapSource/topo.jsp (http://www.garmin.com/cartography/mapSource/topo.jsp)


Sorry, Donít know the program but I wrote such a thing dozen years ago for my own database. I took lat/long coordinates in decimal degrees from the over 3,000 ghost towns locations Iíve collected in Nevada and then plug in a location (like a motel in Fallon) and it will spit out every location within an arbitrary distance. Just wrote it one evening as a console applications, it reads the data one line at a time from a text file (Passed as a command line argument) and outputs to the screen, which I then redirect to a file.Hey Bob! Do I sill owe you an email? I have been out exploring a lot lately and can't remember squat! Anyway, did you ever do any coordinate conversion? Or happen to know any of the formulas for coordinate conversion? I have a dataset (soon to be databased) with both DD and DMS and I am looking to convert all the DD to DMS for display purposes, and at the same time all the DMS to DD for mapping and other purposes. I know there are formulas out there on the web (I have one for JS, but want a Perl or PHP one), I just haven't researched them yet, and this post reminded me of my future plans.


Simple geometry and a little trig if you call Pythagoras' Theorem Trig. ;-)A^2+B^2=C^2 Easiest one to remember! ;-)

*Edit*
The conversion is really easy! Since my server is down and I was bored I looked it up. Taken from: http://www.greasyvalley.com/archives/2004/11/16/convert-lat-long-php/ (http://www.greasyvalley.com/archives/2004/11/16/convert-lat-long-php/)
Say you have 32.872352 lat and -91.632563 long
The whole units of the decimal will remain the same, so
1) multiply the decimal by 60 (0.872352 * 60 = 52.34112), the whole number becomes the minutes (52)
2) take the remaining decimal (0.34112) and multiply by 60, this is now the seconds, round this to two decimal places (0.34221 * 60 = 20.53)
3) string them all together 32 52 20.53

Bob
08-25-2005, 02:41 PM
I agree - code to go from decimal degrees (DD) to degrees/minutes/seconds (DMS) and vice versa is easy. Now if you want to convert different Map Datums (especially the ones from before NAD24 that most GPS oriented programs don't know about) or if you want to take DD or DMS to UTM or back then I do know how to do that and it isn't simple. Every once in a while I have to convert such things. UTM works very well (Many say better) for a limited area (Say the state of Nevada) so many State documents are in UTM. I have a couple functions I wrote (100 lines or so of C Code) lying around somewhere that you call with DD arguments and it returns UTM or you call with UTM and it returns DD for most the recgonized UTMs in the west.

Just picked up a copy of Raymonds 8th Annual Mineral Resources West of the Rocky Mountains 1876 and a couple more early years of USGS Contributions to Economic Geology so I'm far behind (as usual) in my scanning. Need to get some of my "must-do" tasks accomplished but between work, races, and BLM meetings I don't seem to have enough time to get it all done.

Dezdan
08-25-2005, 04:41 PM
Now if you want to convert different Map Datums (especially the ones from before NAD24 that most GPS oriented programs don't know about) or if you want to take DD or DMS to UTM or back then I do know how to do that and it isn't simple. Every once in a while I have to convert such things. UTM works very well (Many say better) for a limited area (Say the state of Nevada) so many State documents are in UTM. I have a couple functions I wrote (100 lines or so of C Code) lying around somewhere that you call with DD arguments and it returns UTM or you call with UTM and it returns DD for most the recgonized UTMs in the west.Nice! I didn't think to look at my dataset to check the datum... I hope all of the merged data I have is from the same datum!


Just picked up a copy of Raymonds 8th Annual Mineral Resources West of the Rocky Mountains 1876 and a couple more early years of USGS Contributions to Economic Geology so I'm far behind (as usual) in my scanning. Need to get some of my "must-do" tasks accomplished but between work, races, and BLM meetings I don't seem to have enough time to get it all done.Are you OCR'ing the scan? If not, I already have a copy scanned in PDF format with an html index. If you are interested in it let me know and I can upload it for you. I also have "Notices of mining machinery and various mechanical appliances in use chiefly in the Pacific states and territories for mining, raising and working ores, with comparative notices of foreign apparatus for similar purposes. By William P. Blake, 1871" in PDF format with an html index. Currently (which means over the last year) I am working on the "Report of J. Ross Browne on the Mineral Resources of the States and Territories West of the Rocky Mountains" 1868, which I believe is pre-Annual editions, but I am not sure.

~Dan

Bob
08-25-2005, 05:35 PM
Dezdan - I scan to tif format so I can later run them through my OCR software but haven't had the time (and maybe not the patience) to OCR yet. I have on of J Ross Brown pre-annual reports but I need to go home to tell ya which one. I also have another or Rossiter Raymonds reports I snarfed of the net. Drop me an email at bob@nvwf.org and I'll let ya know what I find tonight.