Google Maps -> POIs

wibblemonster · Occasional Visitor Joined: Nov 19, 2005 Posts: 31

Tried this on my pc, it seems that the functionality to convert directions works okay on the UK google maps but not for the business search to convert into POI's. Although it does seem to work on the USA maps at google.com

dougconran · Posted: Wed Nov 23, 2005 12:14 pm Post subject:

dougconran · Posted: Wed Nov 23, 2005 12:18 pm Post subject:

gcb · Regular Visitor Joined: Oct 24, 2005 Posts: 151

This sounds really great. Im using IE6.

I put the link in my favourites.
Go to google maps. Type "Swimming pools bradford"
A selection of swimming pools in Bradford are displayed.
I open favourites and click on link, does not seem to work.

Realise , you need to have your favourites displayed , before you make your selection. Brilliant.

Note however, I have noticed that for Google maps in the UK the long lat are only to the nearest 100 meters. Unlike US and Canada which are more acurate. This should improve soon however.

gcb · Regular Visitor Joined: Oct 24, 2005 Posts: 151

OK, Now I am confused. First it did not work, then it worked, then it didnt work again?

Seems to be a quirk with IE6, or google maps. Any ideas anyone know what might be happening.

P.S. Would be good if the postcode was extracted with the description.

wibblemonster · Occasional Visitor Joined: Nov 19, 2005 Posts: 31

It must the the source data on the UK Google maps for business searches as the US maps (google.com) and or UK directions (google.co.uk)work fine and I can only assume that if the US maps on google.com are ok then it cant be the security settings in ie6.

The bookmarklet works every time in ie6 for direction searches on the UK maps but not for business locations searches where it brings up the business search results on the left pane and the locations overlayed on the map on the right pane.

Depending on what bookmarklet I use I either get the same error message as in previous posts or one that say "nothing to extract".

Is there any coding gurus' out their that know whats happening as this is an incredibly useful and easy way of extracting POI's

dougconran · Posted: Wed Nov 23, 2005 8:52 pm Post subject:

OK - I've been playing around a bit with this. As far as I can make out the Google app that processes the search query checks to see what type of browser is being used. If it is one that supports IFRAME it then returns the data in a hidden iframe and this is where GMapToPOI picks the lat & longs up from. If you use an unsupported browser it just returns the data as normal html but then the bookmarklet can't find it because it is looking for the iframe Sad

What I haven't fathomed out is why GMapToPOI can pick up routing but not POIs. It seems to be looking for a <point> tag which I guess is not there but as the iframe is hidden there is no way that I can see what IS there - Oh well Rolling Eyes

Anyone got any ideas because this could be useful.

dougconran · Posted: Thu Nov 24, 2005 12:56 am Post subject:

... and some more.

I think the problem is that there is an error in currmonstor's Javascript although I have no idea what it is.

Anyway, I copied the original and hacked it about a bit and have come up with this which seems to work in Opera but still not in IE6 Bouncing

- Oh well.

I guess there is still an error in the javascript somewhere but I don't use IE Laughing

gcb · Regular Visitor Joined: Oct 24, 2005 Posts: 151

This is all very interesting stuff. It would be great if we could get this resolved.

more info on hidden Iframes please.

mugwump · Occasional Visitor Joined: Sep 11, 2005 Posts: 54

Hi,

Im probably being a bit thick but please would you explain exactly the problem you are trying to resolve, I've played with google maps a bit as they are used on my waypoint converter site which converts postcodes into waypoints and plots them on a google map.

When I coded it everything worked fine in Firefox and I had to recode to get it to work properly with IE, if this is the issue I may be able to help a little...

let me know.
_________________
Apologies to all my supporting users, the http://ukpostcodes.boldlygoingnowhere.org/ postcode converter has now been retired.
The ubiquity of full postcode lookups has made it somewhat redundant. I still have the code if anyone needs it.

mugwump · Occasional Visitor Joined: Sep 11, 2005 Posts: 54

Scratch that, just had another read through the topic and ran some of the examples so I at least understand what you are trying to do. Worked for me by the way (Firefox). I'll go away and have a play with IE
_________________
Apologies to all my supporting users, the http://ukpostcodes.boldlygoingnowhere.org/ postcode converter has now been retired.
The ubiquity of full postcode lookups has made it somewhat redundant. I still have the code if anyone needs it.

gcb · Regular Visitor Joined: Oct 24, 2005 Posts: 151

Pretty good Mugwump, but how about House number and PostCode.

Also, How good is the data on Google-Maps for UK at present. From what I have checked out Google maps is the best available, All other sites can only give GPS locations based on a 100m square grid. But Google Maps is still not as accurate for UK as America and Canada where you can really pin-point a place. Seems they done America and Canada first then the UK.

wibblemonster · Occasional Visitor Joined: Nov 19, 2005 Posts: 31

Just installed Firefox and conversion now works a treat. Just watch for extra comma's in the business descriptions or it will throw out the csv when you try to load it into your GPS or POI edit

mugwump · Occasional Visitor Joined: Sep 11, 2005 Posts: 54

Hi gcb,

I dont use the google map data to generate the waypoints, I generate the waypoints first down to the full accuracy that a postcode will allow *then* plot them on a google map.

As a result any 100m restriction of google in converting/displaying your postcodes is irrelevant. The waypoint the site returns is as good as it can be.

Where did you read about / see the 100m accuracy?

Heres a sample conversion result from 3 sources using the same postcode as input....

Multimap gives
Lat: 51:33:51N (51.5641) Lon: 0:27:20W (-0.4555)

Streetmap gives
Lat: N51:33:51 ( 51.564101 ) Lon: W0:27:20 ( -0.455477 )

Google gives
Lat: 51.564049 Lon:-0.455463

As you can see, the answer from multimap might be viewed as less accurate (it has 2 decimal places less in the response), however because of the vagaries of postcodes and the co-ordinate conversion method you can see that streetmap and google dont agree beyond the accuracy provided by multimap anyway. 8O If you want very acurate positions dont rely on postcodes I guess.
_________________
Apologies to all my supporting users, the http://ukpostcodes.boldlygoingnowhere.org/ postcode converter has now been retired.
The ubiquity of full postcode lookups has made it somewhat redundant. I still have the code if anyone needs it.

gcb · Regular Visitor Joined: Oct 24, 2005 Posts: 151

Streetmap.co.uk well its just useless at finding addresses.

Multimap. When you search by postcode on Multimap. Multimap locates the centre of the area that that postcode refers to. It gives a long , lat and coresponding X,Y. The long and lat only change when X and Y change. The long and lat correspond to the centre of that 100m square. The post code may cover areas outside the 100m square, The accuracy is not so good.

Google Maps for the USA and Canada seem to be very accurate as can be seen if you use this site http://geocoder.ca/

Type Wellington 3 Ottowa On. Now change the number incrementally 2,3,4 and see the long lat change acordingly and the arrow head moves down the street.

Multimap does not do this because the long Lat are only from the postcode not the house number as well.

This Canadian site uses a geocoder registered with google maps, I thought this was the way you were getting your data?

I read all the stuff on geocoder.us but Im not realy a web apps person and dont have my own website.

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