Language - Python

From Phidgets Support
Revision as of 19:50, 7 February 2012 by Mphi (talk | contribs) (→‎Mono)

Python Python is an object oriented programming language developed by the Python Software Foundation, is powerful and easy to learn.

Introduction

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Quick Downloads

Just need the Python documentation, drivers, libraries, and examples? Here they are:

API Documentation:

Example Code:

Libraries and Drivers:

Getting started with Python

If you are new to writing code for Phidgets, we recommend starting by running, then modifying existing examples. This will allow you to:

  • Make sure your libraries are properly linked
  • Go from source code to a test application as quickly as possible
  • Ensure your Phidget is hooked up properly

Instructions are divided up by operating system. Choose:

Windows(2000/XP/Vista/7)

Description of Library

C# programs on Windows depend on the following files, which the installers above put onto your system:

  • phidget21.dll contains the actual Phidgets library, which is used at run-time. By default, it is placed in C:\Windows\System32.

You will also need one of the following two files, depending on the .NET framework version you are targeting:

  • Phidgets Python Module is the Phidgets library for Python 2.5 or higher. Your compiler has to know where this file is.

If you do not want to use our installer, you can download the five file files.


Running the examples and writing your own code can be fairly compiler-specific, so we include instructions for each compiler below.

IDLE

Use Our Examples

Please start by downloading Phidgets Python Module. Extract the file, you will find a directory namedPhidgets. Copy this directory over to the <Python Install Directory>\Lib\site-packages directory.

Next, download the examples and unpack them into a foler. While these examples were written in Python 3.0, they are also compatible with Python and 2.5 and 2.6.

If you aren't sure what the software example for your device is called, check the software object listed in the Getting Started guide for your device. Open the example in the IDLE editor

The only thing left to do is to run the examples! Click on Run → Run Module

Run‎

Once you have the Python examples running, we have a teaching section below to help you follow them.

Write Your Own Code

When you are building a project from scratch, or adding Phidget function calls to an existing project, you'll need to configure your environment to properly link the Phidget Python libraries. Please see the Use Our Examples section for instructions.

Then, in your code, you will need to reference to the Phidgets Python library.

from Phidgets.PhidgetException import PhidgetErrorCodes, PhidgetException
from Phidgets.Events.Events import AttachEventArgs, DetachEventArgs, ErrorEventArgs, InputChangeEventArgs, OutputChangeEventArgs, SensorChangeEventArgs
from Phidgets.Devices.InterfaceKit import *

The project now has access to the Phidget21 function calls and you are ready to begin coding.

The same teaching section which describes the examples also has further resources for programming your Phidget.

Eclipse with PyDev

Use Our Examples

Please start by downloading Phidgets Python Module. Extract the file, you will find a directory namedPhidgets. Copy this directory over to the <Python Install Directory>\Lib\site-packages directory.

Next, download the examples and unpack them into a foler. While these examples were written in Python 3.0, they are also compatible with Python and 2.5 and 2.6.

If you aren't sure what the software example for your device is called, check the software object listed in the Getting Started guide for your device. Open the example in the IDLE editor

Next, a new project will need to be created. Generate a new PyDev project with a descriptive name such as PhidgetTest

New Project

To import the example program into your project, create a new .py file in the project.

New File

Copy and paste the contents of the example .py into the new file

The only thing left to do is to run the examples! Click on Run → Run Module

Run‎

Once you have the Python examples running, we have a teaching section below to help you follow them.

Write Your Own Code

When you are building a project from scratch, or adding Phidget function calls to an existing project, you'll need to configure your development environment to properly link the Phidget Python libraries. Please see the Use Our Examples section for instructions.

Then, in your code, you will need to include the Phidget library:

from Phidgets.PhidgetException import *
from Phidgets.Events.Events import *
from Phidgets.Devices.InterfaceKit import

The project now has access to the Phidget21 function calls and you are ready to begin coding.

The same teaching section which describes the examples also has further resources for programming your Phidget.

MonoDevelop

Use Our Examples

Download the examples and unpack them into a folder. Here, you can find example programs for all the devices. These examples were written in Visual Studio 2005 and 2008, but are also compatible with MonoDevelop.

To load all projects in MonoDevelop, go to File → Open, and open AllExamples/AllExamples.sln

This will load all of the examples available for C#, and then you can set your main project to be the one that matches your device. If you aren't sure what the software example for your device is called, check the software object listed in the Getting Started guide for your device. If you are running under the .NET framework, you can use either the full or simple examples. Otherwise, if you are running under the Mono framework, please only use the simple examples. The full examples uses Windows Forms, which is not completely compatible with Mono's Gtk#.

Start Up Project

The only thing left to do is to run the examples! Right click the project, and click on Run With and select the target framework. Please note that the projects, by default try to find the Phidget21.NET.dll in the C\Program Files\Phidgets. If you have it installed in another location, please change the path to the file's location accordingly. If you are receiving an error message regarding that the namespace Phidgets cannot be found, please re-add the reference to Phidget21.NET.dll. Please see the Write Your Own Code section for details.

Run As

Once you have the C# examples running, we have a teaching section below to help you follow them.

Write Your Own Code

When you are building a project from scratch, or adding Phidget function calls to an existing project, you'll need to configure your development environment to properly link the Phidget C# libraries. To begin:

1. Create a new C# empty project with a descriptive name such as PhidgetTest.

New Project

2. Add a reference to the .NET library.

Add Reference

3. Select Phidget21.NET.dll. If you used our installer, by default, this file is placed in C:\Program Files\Phidgets. If it is in another location, please change the path to the file's location accordingly.

Add Reference

4. Then, in your code, you will need to include the Phidget library:

  using Phidgets;
  using Phidgets.Events;

The project now has access to the Phidget21 function calls and you are ready to begin coding.

The same teaching section which describes the examples also has further resources for programming your Phidget.

Mac OS X

Python has excellent support on Mac OS X.

The first step in using Python on Mac is to install the Phidget libraries. Compile and install them as explained on the getting started guide for your device. Then, the OS - Mac OS X page also describes the different Phidget files, their installed locations, and their roles....

Linux

Python has support on Linux.

The first step in using Python on Linux is to install the Phidget libraries. Compile and install them as explained on the main Linux page. That Linux page also describes the different Phidget files, their installed locations, and their roles.

Follow The Examples

By following the instructions for your operating system and compiler above, you probably now have a working example and want to understand it better so you can change it to do what you want. This teaching section has resources for you to learn from the examples and write your own.

Next, comes our API information. These resources outline the Python Phidget functions:

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Example Flow

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Code Snippets

Common Problems and Solutions/Workarounds

Here you can put various frequent problems and our recommended solutions.