Point storage format: lat/lon or lon/lat? [closed] - gis

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First time user of PostGIS here.
I've been inserting my POINT fields in the conventional lat/lon order for a while now but it seems like when I explore PostGIS, it launches a map and it appears that the coordinates are read in lon/lat format, meaning everything is off from what I initially thought. I notice this is the case in Django admin as well for PointField.
Does PostGIS enforce a particular order or is the order up to me? Are there any repercussions from storing them as lat/lon, e.g. will distance calculations be off?

PostGIS's ST_MakePoint expects (x, y) order, which corresponds to (longitude, latitude) order. Storing it in reverse order would simply be incorrect.
There's some good reading here: https://macwright.org/lonlat/
I personally advocate for lon/lat order in general, since that is equivalent to the mathematical x/y convention. But in any case, you must always verify with the software you are using; you don't get to pick.

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Download roads network from OpenStreetMap and simplify graph of roads [closed]

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I exported the roads network from OpenStreetMap. I took ways, their corresponding nodes and plotted them:
I would like to have this graph simplified, here is my desired output (yellow ellipses are nodes and green lines are edges):
I didn't manage to find a tool (or option) that "makes network smoother"? Of course, an option would be to program the solution by myself, but before doing that I would like to know if I am not trying to re-invent the wheel.
Does anyone know if there is an easy option to obtain that?
If you are willing to use Java (or another JVM-based language) there is a tool called Atlas which has an option called BigNode which does mostly what you need.
Once you export your OSM data to the Atlas format, you can invoke all the BigNodes in that Atlas and it will group all the nodes at similar intersections for you and provide navigable in/out paths through each.

Is there a better solution than google speech-api? [closed]

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I'm working on Sbire which use google speech-api. There is a some things which I don't like with this api.
First, this is not in streaming mode. It receive small audio files but there is no real pipes.
Secondly, it's not precise. Google does not record our voice to learn our accent. I think it's very important to have a good quality of recognition.
I'm looking for a free api or an open-source tool.
Actually there is a streaming mode, but it requires an API key. Here is an example of how to use it: http://mikepultz.com/2013/07/google-speech-api-full-duplex-php-version/
If you want something that learns, you'll need to create a neural network to handle the data. The best open source tool, however, is CMUSphinx or pocketSphinx(a mini version of CMUSphinx). Here is a link to that tool: http://sourceforge.net/p/cmusphinx/code/HEAD/tree/trunk/
The best part of CMU-Sphinx, however, is that you can set a dictionary of keywords. Instead of outputting gibberish, you can have it ONLY output those commands and finds the command closest to what it thinks you are saying. This make speech recognition incredibly accurate, but only work for a small set of words.

Are there any good opensource geoparsers available? [closed]

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Are there any good opensource Geoparsers? There are several free solutions (services) available (e.g. Yahoo's placemaker, EDINA's Unlock Text) but they do not appear to be opensource.
Ideally the parser should be aimed to mine location information from arbitrary text (as opposed to expect input to be a location, like Google's Geo Coding API or GeoName's search API but such suggestions are welcome as well.
Thanks in advance.
Related question on SO: Identifying geographical locations in text
UPDATE:
Apparently Unlock Text is based on "Edinburgh Geoparser" which is open source (GPL) but not currently publicly downladable (source).
Fairly recent evaluation of geoparsers: http://www.scribd.com/doc/41603112/geoparser
This one seems pretty cool, but the implementation assumes the address to be US address: http://openblockproject.org/docs/index.html
List of parsers found so far:
- JGeocoder http://jgeocoder.sourceforge.net/parser.html
- Gisgraphy http://www.gisgraphy.com/
- Geotools http://www.geotools.org/
(geotools does not seem to provide geocoding (http://osgeo-org.1560.n6.nabble.com/Review-or-Suggestion-for-Geocoding-Service-in-US-td4991055.html))
Some other resources:
- http://www.osgeo.org/
- http://lin-ear-th-inking.blogspot.co.uk/2010/03/open-source-geocoders.html
- http://lin-ear-th-inking.blogspot.co.uk/2010/03/more-open-source-geocoders.html
- Reverse geotagging
- Geohack
CLAVIN seems like a possible option.
From the website: "CLAVIN (Cartographic Location And Vicinity INdexer) is an award-winning open source software package for document geotagging and geoparsing that employs context-based geographic entity resolution."

API to type city name and get a list of possible cities? [closed]

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I need to know on which city my users are.
I cannot use a regular text input since there are similar named cities and users can call the same city by different names,.
I want to let users type their city and display a list of similar results, I could do it with a world cities database, jquery and sql but I'm really not dying to do it from a scratch.
Is there any api (e.g: google) that has an unique ID for each city in the world and let's you search them? Could you post a link to a similar implementation?
There is the Google Places Autocomplete API,
https://developers.google.com/places/documentation/autocomplete
and a library for Maps Version 3 at https://developers.google.com/maps/documentation/javascript/places#places_autocomplete
but I don't know how well it will cope with different names for the same city — although, having tried it, it does present Munich, Germany for munchen — see how well your use case performs.

Most accurate open-source OCR for handwritten numbers? [closed]

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My software needs to read a fixed-length handwritten number.
While I could use a general-purpose library like Tesseract, I am sure there is something smarter. Tesseract will probably misinterpret some of the 1 or 7 as I or l, whereas a software that expects only numbers would not.
Knowing that there are only numbers (American-English way of writing them), the algorithm could focus on 10 potential matches instead of hundreds of symbols.
Any experience OCRing handwritten number-only fields?
What open source library/software did you get the best results with?
From the FAQ of Tesseract:
How do I recognize only digits?
In 2.03 and above:
Use
TessBaseAPI::SetVariable("tessedit_char_whitelist", "0123456789");
before calling an Init function or put this in a text file called tessdata/configs/digits:
tessedit_char_whitelist 0123456789
and then your command line becomes:
tesseract image.tif outputbase nobatch digits
Warning: Until the old and new config variables get merged, you must have the nobatch parameter too.
But I think since it was designed for printed—not handwritten—text, accuracy might suffer even for digits only.