Lecture # 27 Python I

Python “Interpretive” language (vs. compiled) So is HTML, JavaScript. Python supports file I/O. JavaScript doesn’t Python is a serious web programming language used by Google, ILM, etc.

Jython Jython is a “dialect” of Python Python is implemented in C Jython is implemented in Java We use JES JES = Jython Environment for Students

Downloading Jython jes/downloads/list

Using Jython Select JES from “Programs” Click on the black part of the UI after the command prompt >>>

Jython DEMO print print “Hello” x = print x message = “Hello There” print message

Jython DEMO print print “Hello” x = print x message = “Hello There” print message Note: Python is case sensitive. “Print” and “Message” won’t work.

Jython DEMO Pictures pickAFile()

Jython DEMO Pictures pickAFile() print pickAFile()

Jython DEMO Pictures pickAFile() print pickAFile() file = pickAFile()

Jython DEMO Pictures pickAFile() print pickAFile() file = pickAFile() print file

Jython DEMO Pictures pickAFile() print pickAFile() file = pickAFile() print file pict=makePicture(file) # interpret as picture

Jython DEMO Pictures pickAFile() print pickAFile() file = pickAFile() print file pict=makePicture(file) # interpret as picture show(pict) # display as picture

How could we do this all at once?

show(makePicture(pickAFile()))

How could we do this all at once? show(makePicture(pickAFile())) Now lets save it as a Python Program: displayPict.py

How could we do this all at once? show(makePicture(pickAFile())) Now lets save it as a Python Program: displayPict.py And run it: open it and load it

How could we do this all at once? show(makePicture(pickAFile())) Now lets save it as a Python Program: displayPict.py And run it: open it and load it King of the “1-liners”

Jython DEMO Sound file = pickAFile() print file sound=makeSound(file) # interpret as sound play(sound) # lets listen to it All together: play(makeSound(pickAFile())) Save as a Python program and run it

Jython Functions def myFunction(): colon

Jython Functions def myFunction(): colon parentheses

Jython Functions def myFunction(): colon parentheses function name

Jython Functions def myFunction(): colon parentheses function name “def” instead of “function()”

Jython Functions def myFunction(): colon parentheses function name “def” instead of “function()” The function must be called somewhere

Jython Functions def myFunction(): block of commands

Jython Functions def myFunction(): block of commands Note indentation!

Jython Functions: Indentation Indentation is critical in Python Indentation associates these commands with this function Indentation separates commands from other functions

Jython Function: Example def pickAndShow(): file = pickAFile() myPict = makePicture(file) show(myPict) pickAndShow()# somewhere we have to call the function