python - lat/lon to utm to lat/lon is extremely flawed, how come? -

-

i've tried following, input: lat/lon data i'll calculate box around by, let's 50 m, +/- 50 m on easting/northing value.

now reconvert lat/lon , script:

http://robotics.ai.uiuc.edu/~hyoon24/latlongutmconversion.py result can't be, lon before around 7, afterwards around 2. 

zone, easting, northing = lltoutm(23, location.get_lat(), location.get_lon())   toputm = northing + error bottomutm = northing - error leftutm = easting - error rightutm = easting + error left, top = utmtoll(23, leftutm, toputm, zone)

is error in code, or might script flawed?

so i've tried use pyproj, lat/lon utm lat/lon see happens

>>> p = pyproj.proj(proj='utm', zone=32, ellps='wgs84') >>> p <pyproj.proj object @ 0x7ff9b8487dd0> >>> x,y = p(47.9941214, 7.8509671) >>> print x,y 5159550.36822 1114087.43925 >>> print p(x,y,inverse=true) (47.971558538495991, 7.8546573140162605)

and here it's not extremely far off script above, still seems enough incorrect not able use it. how come? can more exact results?

edit:

i ran test() , tests passed.

in epsg file there no such thing. closest i've found this:

<32632> +proj=utm +zone=32 +ellps=wgs84 +datum=wgs84 +units=m +no_defs <>

no tmerc. need pass towgs84 parameters? ones above?

i've created small utm conversion library python last week , uploaded python package index: http://pypi.python.org/pypi/utm

i have compared using pyproj , faster , more accurate. given sample data, result:

>>> import utm  >>> u = utm.from_latlon(47.9941214, 7.8509671) >>> print u (414278, 5316285, 32, 't')  >>> print utm.to_latlon(*u) (47.994157948891505, 7.850963967574302)

update: richards answer below describes real solution issue.


Comments

Post a Comment

Popular posts from this blog

linux - Using a Cron Job to check if my mod_wsgi / apache server is running and restart -

-
my group , running server based upon django , uses mod_wsgi run apache server. not working on project after over, attempting set cronjob similar functionality check if apache server has shut down(system restart or power failure), , if has, restart server me. i've found documentation on how check if apache server down , restart server if is, our server uses https , our start command pretty verbose. can use functionality provided in these examples: https://askubuntu.com/questions/277389/cron-job-to-restart-apache https://www.digitalocean.com/community/tutorials/how-to-use-a-simple-bash-script-to-restart-server-programs or need more complicated process make happen? the command use start server is python manage.py runmodwsgi --host 0.0.0.0 --port 8001 --https-port 8000 --ssl-certificate (certificate location) --server-name (domain name) i'm pretty new linux , using both mod-wsgi apache appreciated. you better off using --setup-only option mod_wsgi-expres...
Read more

actionscript 3 - TweenLite does not work with object -

-
i got following problem: i have object called tempscore game. this object blitted canvas renderer via copypixels method. object not display object. it's score-object (self made). score-object extends object called basicblitarrayobject. basicblitarrayobject extends eventdispatcher (therefore no display object). i tried apply several different tweenlite-plugins tempscore-object (i.e. transformaroundcenter, colormatrixfilter, etc.). nothing happens. absolutely nothing. sometimes error messages (when plugin requires display object , object not display object). far good. according greensock (maker of tweenlite) engine can tween numeric property of object. when plugin transformaroundcenter requires display object tweening have modify plugin working non-display object (tempscore). can't because it's way hard me. my game rests upon code: http://www.8bitrocket.com/book/ch11_blastermines.zip try apply tweenlite object called tempmine inside game class blastermines. ...
Read more

jQuery Ajax Render Fragments OR Whole Page -

-
i'm in throes of building application wraps mess of legacy code. page working on, need substitute fragment divs constructed on back-end -- or else need replace entire page altogether. idea there dynamically controlled flow needs satisfied before can forward legacy product. substituting fragments works fine, seen in below my_body_content swap. trouble comes when i'm trying render not fragment, whole page, in "body" swap. @ point page goes blank. i want similar errors returned server. want nice rest 404 error messages displayed on screen, legacy-product 404s show in legacy-product 404 page. yes, requirements project weird. that's not problem can fix. here's jquery invocation, names changed protect guilty: $.ajax({ url: "places/things", type: "post", data: json.stringify(somebadassobject), datatype: "text", accepts: "text/html", contenttype: "application/json; charset=...
Read more