46 lines
1.3 KiB
Plaintext
46 lines
1.3 KiB
Plaintext
What is Python?
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---------------
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Python is an interpreted, interactive, object-oriented programming
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language. It incorporates modules, exceptions, dynamic typing, very
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high level dynamic data types, and classes. Python combines
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remarkable power with very clear syntax. It has interfaces to many
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system calls and libraries, as well as to various window systems, and
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is extensible in C or C++. It is also usable as an extension language
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for applications that need a programmable interface. Finally, Python
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is portable: it runs on many brands of UNIX, on the Mac, and on
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MS-DOS.
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As a short example of what Python looks like, here's a script to
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print prime numbers (not blazingly fast, but readable!). When this
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file is made executable, it is callable directly from the UNIX shell
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(if your system supports #! in scripts and the python interpreter is
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installed at the indicated place).
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#!/usr/local/bin/python
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# Print prime numbers in a given range
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def main():
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import sys
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min, max = 2, 0x7fffffff
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if sys.argv[1:]:
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min = int(eval(sys.argv[1]))
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if sys.argv[2:]:
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max = int(eval(sys.argv[2]))
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primes(min, max)
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def primes(min, max):
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if 2 >= min: print 2
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primes = [2]
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i = 3
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while i <= max:
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for p in primes:
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if i%p == 0 or p*p > i: break
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if i%p <> 0:
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primes.append(i)
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if i >= min: print i
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i = i+2
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main()
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