Python

1
Python

• Henry Armstrong
• Andy Burras
• Everett Hite

2
History

• First released in 1991 by Guido van Rossum
• Designed around a philosophy which emphasized
  readability and importance of programmer effort
  over computer effort
• Minimalist syntax and semantics
• Large standard library is comprehensive
• It was influenced by ALGOL 68, C, Lisp, Perl and
  Java
• It was originally developed for UNIX scripting,
  but eventually grew beyond these bounds

3
Concepts

• Multi-paradigm language focusing on functional,
  object oriented and imperative
• Has a fully dynamic type system. This means that
  type checking is done during runtime
• Variables are strongly typed. This forbids
  operations which make little or no sense (i.e.
  cannot perform int char)
• Has automatic memory management
• Has a highly readable, uncluttered language. Uses
  many English keywords where other languages use
  punctuation

4
Implementations

• YouTube and the original BitTorrent client were
  programed in python.
• Google and NASA use python for a variety of
  things
• Python is embedded in a number of software
  packages including ArcGIS (a GIS package) and
  Maya (a high-end 3D animation package)
• Python is also used for scripting in a number of
  video games, including Civilization IV, Eve
  Online and Battlefield 2

5
Code Example
print "This is a factorial program. n -1
Initialize n for error checking while n lt 0
Ensure that only nonnegative numbers will be
accepted n input( "What number do you want
to factorialize?" ) temp n Initialize
return value (temp) and the counter count n
1 if n 0 Account for special case 0!
1 set temp, count to 1 temp 1 count
0 while count gt 0 Calculate n factorial
temp temp count count count 1 print
n,"! ",temp Print result
6
Comparison to Other Languages
The following programs will count from 0 to
1000000 and print them out to a file
Java import java.io. public class test
public static void main(String args) try
File f new File("/tmp/scratch")
PrintWriter pw new PrintWriter(new
BufferedWriter( new
FileWriter(f))) for(int i 0 i lt
1000000 i) pw.print(i)
pw.close() catch(IOException ioe)
ioe.printStackTrace()
Python fopen(/tmp/scratch,wb) For i in
xrange(1000000) f.write(str(i)) f.close()
C include ltiostream.hgt include
ltfstreamgt using namespace std int main(int
argc, char argv) ofstream out
out.open("/tmp/scratch") for(int i 0 i lt
1000000 i) out ltlt i out.close()
7
Comparisons (contd)

• To Java
• Python typically run slower than equivalent Java
  programs
• The development process for Python is
  significantly shorter than that of Java
• Actual code length of Python is 3-5 times shorter
  than equivalent Java code
• To C
• Python compared to C is similar to Python
  compared to Java, just to a greater extent.
• Actual code length of Python is 5-10 times
  shorter than equivalent C code
• Python is sometimes referred to and used as a
  glue language that combines several component
  written in C
• To Perl
• Both share similar roots (Unix, scripting), and
  similar features.
• Perl is harder to maintain based off the
  sometimes cryptic syntax and multiple operators

8
SOURCES

• http//www.razorvine.net/python/PythonComparedToJa
  va
• http//www.wikipedia.com/Python_(programming_langu
  age)
• http//furryland.org/mikec/bench
• http//www.python.org