Hi all
Can any one explain me in a few words what I am talking about?
I think that I understand that ctypes permit python to use external resources and, i.e. use C code with in the python code.

I have created (mostly copy/paste from examples) a little program that shows time stamp and speed in an endless loop.

The thing is that location.py can query gps reported speed as a max rate of one query per second, so, I sometimes get 10kmh increments and I can not create a detailed graphic, of the speed of my car from 0 to 100kmh (60mph) over time. I want to create an acceleration curve over time. I will also try shifting the gearbox at a different rpms and see how it affects acceleration.

The point is, how can I get speed from gps faster than 1 time per second? I think the answer is going around location.py limitation and that is using ctypes, but I don't know where to begin. I have red a few tutorial but I don't fully understand it yet and I have no idea at all of how to query gps info via ctypes.

Here is my code:
http://talk.maemo.org/showthread.php?t=47473

Any help is welcome

dhcmega

Once per second is a hardware limitation. Most GPS chips, until recently, only compute the position once per second. Chips which produce more readings per second are available, but would be bad in a phone, since they probably need more power.

Note also that GPS speed is not accurate at low speeds, particularly below 3 MPH or so. Since you are trying to measure acceleration you should be using the accelerometer, it has an update rate of 20Hz, and is very easy to read from python.

Hi
I have red that PyS60 for the N95 allows a far more faster rate, could it be (5Hz).

I know it take a lot of power, but it will only be for short amounts of time. Besides, programmer should decide if is it worth to use or not more power, and no a default limitation. If you are doing a maps positioning you will not need more than 1 per second, but if you try something more specific or something like me right now it will be impossible.

How can I use the accelerometer to know my speed? I will be able to know the acceleration but not the actual speed, unless it can be calculated based in acceleration and time elapsed...

Thanks for your answer