Google Weather API - parsing and modifying data

Question

This question is no longer up-to-date -- Google shut down the unofficial weather API in 2012

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I\'d like to put some weather forecast to a

Answer 1

The google xml does return the temperature in Celsius as well look for a temp_c tag inside current_conditons

Answer 2

Encoding problem:

For some reason Google returns the XML content without proper encoding declaration. One would expect something like:

<?xml version='1.0' encoding='ISO-8859-2'?>

But they skip the encoding attribute in the header. This makes the simplexml_load_file function assume the default encoding of UTF-8. I would consider this a bug in their API implementation, since the XML spec defines UTF-8 as the fallback default encoding.

To compesate for this, try something like:

<?php
$URL = "http://www.google.com/ig/api?weather=koprivnica,croatia&hl=hr";
$dataInISO = file_get_contents($URL);
$dataInUTF = mb_convert_encoding($dataInISO, "UTF-8", "ISO-8859-2");
$xml = simplexml_load_string($dataInUTF);
...

Which seems to work. The ISO-8859-2 value was a pure guess.

Fahrenheit/Celsius:

I don't see an easy way to request the temperature data to be provided in Celsius instead of Fahrenheit in this API (I couldn't find the official doc, am I blind?). However conversion from F to C shouldn't be hard at all.

Try this formula:

(°F  -  32)  x  5/9 = °C

which you can find in thousand of places. I took it from http://www.manuelsweb.com/temp.htm