ls scripts/hello-world*.py

cat scripts/hello-world.py

!python scripts/hello-world.py

cat scripts/hello-world-in-arabic.py

!python scripts/hello-world-in-arabic.py

import math

import math

x = math.cos(2 * math.pi)

print(x)

from math import *

x = cos(2 * pi)

print(x)

from math import cos, pi

x = cos(2 * pi)

print(x)

from math import cos as cos1
import math as ma

x = cos1(2 * ma.pi)

print(x)

import math

print(dir(math))

help(math.log)

log(10)

log(10, 2)

%load solutions/getting_help.py

from os import getcwd

help(getcwd)

print(getcwd())


# variable assignments
x = 1.0
my_variable = 12.2

type(x)

x = 1

type(x)

print(y)

# integers
x = 1
type(x)

# float
x = 1.0
type(x)

# boolean
b1 = True
b2 = False

type(b1)

# complex numbers: note the use of `j` to specify the imaginary part
x = 1.0 - 1.0j
type(x)

print(x)

print(x.real, x.imag)

import types

# print all types defined in the `types` module
print(dir(types))

x = 1.0

# check if the variable x is a float
type(x) is float

# check if the variable x is an int
type(x) is int

isinstance(x, float)

x = 1.5

print(x, type(x))

x = int(x)

print(x, type(x))

z = complex(x)

print(z, type(z))

x = float(z)

y = bool(z.real)

print(z.real, " -> ", y, type(y))

y = bool(z.imag)

print(z.imag, " -> ", y, type(y))

1 + 2, 1 - 2, 1 * 2, 1 / 2

1.0 + 2.0, 1.0 - 2.0, 1.0 * 2.0, 1.0 / 2.0

# Integer division of float numbers
3.0 // 2.0

# Note! The power operators in python isn't ^, but **
2 ** 2

True and False

not False

True or False

2 > 1, 2 < 1

2 > 2, 2 < 2

2 >= 2, 2 <= 2

# equality
[1,2] == [1,2]

# inequality
1 != 1

# objects identical?
l1 =[1,2]
l2 = l1
l1 is l2

a = 15
b = 5
c = 2.2

# expression evaluation here
val = 0

print(val)

%load solutions/operators.py

a = 15
b = 5
c = 2.2

# expression evaluation here
val = (float(5*(a>b)) + float(2*(a<(b*4))))/float(a) * c

print(val)


s = "Hello world"
type(s)

s1 = "KAUST's hello world"
print(s1)
s2 = 'He said "Hello"'
print(s2)

# length of the string: the number of characters
len(s)

# replace a substring in a string with somethign else
s2 = s.replace("world", "test")
print(s2)

s[0]

s[0:5]

s[:5]

s[6:]

s[:]

s[:-2]

s[-1], s[-2]

s[::1]

s[::2]

print(dir(str))

import math
print 'The value of %5s is approximately %5.3f.' % ('PI', math.pi)

print('1234'.zfill(7))
print('-3.14'.zfill(7))
print('1234'.zfill(2))

print str(1).rjust(2), str(1**2).rjust(3),str(1**3).rjust(4)
print str(5).rjust(2), str(5**2).rjust(3),str(5**3).rjust(4)
print str(10).rjust(2), str(10**2).rjust(3),str(10**3).rjust(4)

print('We are the {} who say "{}!"'.format('knights', 'Ni'))

print('{0} and {1}'.format('spam', 'eggs'))
print('{1} and {0}'.format('spam', 'eggs'))

print( 'This {food} is {adjective}.'.format(food='spam', adjective='absolutely horrible') )

print( 'The story of {0}, {1}, and {other}.'.format('Bill', 'Manfred', other='Georg') )

import math
print( 'The value of PI is approximately {0:.3f}.'.format(math.pi) )

name1 = 'Sjoerd'
phone1 = 4127
name2 = 'Jack'
phone2 = 4098
name3 = 'Dcab'
phone3 = 7678

print( '{0:10} ==> {1:10d}'.format(name1, phone1) )
print( '{0:10} ==> {1:10d}'.format(name2, phone2) )
print( '{0:10} ==> {1:10d}'.format(name3, phone3) )
    



%load solutions/strings.py

s = 'Hello world'

s = s.replace('o', 'a')

s = s[:6].lower() + s[6:].upper() 

print(s[3:-1])


l = [1,2,3,4]

print(type(l))
print(l)

print(l)

print(l[1:3])

print(l[::2])

l[0]

l = [1, 'a', 1.0, 1-1j]

print(l)

nested_list = [1, [2, [3, [4, [5]]]]]

print(nested_list)

nl = [1, [2, 3, 4], [5, [6, 7, 8]]]

print(nl)
print(nl[0])
print(nl[1][1])
print(nl[2][1][2])


start = 10
stop = 30
step = 2

range(start, stop, step)

# in python 3 range generates an interator, which can be converted to a list using 'list(...)'. It has no effect in python 2
list(range(start, stop, step))

list(range(-10, 10))

s

# convert a string to a list by type casting:

s2 = list(s)

s2

# sorting lists
s2.sort()

print(s2)

# create a new empty list
l = []

# add an elements using `append`
l.append("A")
l.append("d")
l.append("d")

print(l)

l[1] = "p"
l[2] = "p"

print(l)

l[1:3] = ["d", "d"]

print(l)

l.insert(0, "i")
l.insert(1, "n")
l.insert(2, "s")
l.insert(3, "e")
l.insert(4, "r")
l.insert(5, "t")

print(l)

l.remove("A")

print(l)

del l[7]
del l[6]

print(l)

l1 = [1, 2, 3] + [4, 5, 6]
print(l1)

l2 = [1, 2, 3] * 2
print(l2)

a = [1, 2, 3]
b = a
print("a is b? ", a is b)
b[0] = -1
print("a = ", a)
print("b = ", b)

a = [1, 2, 3]
b = a[:] # or:
print("a is b? ", a is b)
c = list(a)
b[0] = -1
c[1] = -1
print("a = ", a)
print("b = ", b)
print("c = ", c)


a = [ [1, 2, 3], 4, 5]
b = a[:]
c = list(a)
a[0].append(-1)
print("a = ", a)
print("b = ", b)
print("c = ", c)

from copy import deepcopy
a = [ [1, 2, 3], 4, 5]
b = deepcopy(a)
a[0].append(-1)

print("a = ", a)
print("b = ", b)




%load solutions/lists.py

l = range(5,16,2)
print(l)

l[-1] = range(4,9,2)
print(l)

l[-1][-2] = -1
print(l)

del l[1:4]
print(l)

l.insert(1, 'Hello')
print(l)


point = (10, 20)

print(point, type(point))

point = 10, 20

print(point, type(point))

x, y = point

print("x =", x)
print("y =", y)

point[0] = 20

params = {"parameter1" : 1.0,
          "parameter2" : 2.0,
          "parameter3" : 3.0,
           1: 4.0, 
           (5, 'ho'): 'hi'}

print(type(params))
print(params)

print("parameter1 = " + str(params["parameter1"]))
print("parameter2 = " + str(params["parameter2"]))
print("parameter3 = " + str(params["parameter3"]))

params["parameter1"] = "A"
params["parameter2"] = "B"

# add a new entry
params["parameter4"] = "D"

print("parameter1 = " + str(params["parameter1"]))
print("parameter2 = " + str(params["parameter2"]))
print("parameter3 = " + str(params["parameter3"]))
print("parameter4 = " + str(params["parameter4"]))
print("'key 1' = " + str(params[1]))
print("'key (5, 'ho')' = " + str(params[(5, 'ho')]))

del params["parameter2"]
print(params)



%load solutions/dicts.py

d = {('John', 'Smith'):30,
     ('Ahmad', 'Said'):22,
     ('Sara', 'John'):2
     }
print(d)

john = ('John', 'Smith')
d[john] = d[john] + 1
print(d)

d[('Ahmad', 'Ahmad')] = 19
print(d)

del d[('Sara','John')]
print(d)


statement1 = False
statement2 = False

if statement1:
    print("statement1 is True")
    
elif statement2:
    print("statement2 is True")
    
else:
    print("statement1 and statement2 are False")

statement1 = statement2 = True

if statement1:
    if statement2:
        print("both statement1 and statement2 are True")

# Bad indentation!
if statement1:
    if statement2:
    print("both statement1 and statement2 are True")  # this line is not properly indented

statement1 = False 

if statement1:
    print("printed if statement1 is True")
    
    print("still inside the if block")

x = 10
y = 5

if x > y:
    print(float(x)/y)
elif x == y:
    print(1)
else:
    print(float(y)/x)
            

if statement1:
    print("printed if statement1 is True")
    
print("now outside the if block")

# a compact way for using the if statement
a = 2 if statement1 else 4
print("a= ", a)


name = 'john'
if name in ['jed', 'john']:
    print("We have Jed or John")
   
num = 1
if num in [1, 2]:
    print("We have 1 or 2")

for x in [1,2,3]:
    print(x)

for x in range(4): # by default range start at 0
    print(x)

for x in range(-3,3):
    print(x)

for word in ["scientific", "computing", "with", "python"]:
    print(word)

for key, value in params.items():
    print(key + " = " + str(value))

for idx, x in enumerate(range(-3,3)):
    print(idx, x)

l1 = [x**2 for x in range(0,5)]

print(l1)

# Nested list comprehensions
l2 = [(x, y) for x in range(0,5) for y in range(5,10)]

print(l2)

#List comprehensions with conditional statement
l1 = [x**2 for x in range(0,5) if x != 2]

print(l1)

i = 0

while i < 5:
    print(i)
    
    i = i + 1
    
print("done")

words = ["Aerial", "Affect", "Agile", "Agriculture", "Animal", "Attract", "Audubon",
         "Backyard", "Barrier", "Beak", "Bill", "Birdbath", "Branch", "Breed", "Buzzard",
         "The", "On", "Upper", "Not", "What", "Linked", "Up", "In", "A", "lol"]

%load solutions/control_flow.py

d = {}
for w in words:
    if len(w) > 2:
        if len(w) in d:
            d[len(w)].append(w)
        else:
            d[len(w)] = [w]
print d


def func0():   
    print("test")

func0()

def func1(s):
    """
    Print a string 's' and tell how many characters it has    
    """
    
    print(s + " has " + str(len(s)) + " characters")

help(func1)

func1("test")

def square(x):
    """
    Return the square of x.
    """
    return x ** 2

square(4)

def powers(x):
    """
    Return a few powers of x.
    """
    return x ** 2, x ** 3, x ** 4

powers(3)

x2, x3, x4 = powers(3)

print(x3)

def myfunc(x, p=2, debug=False):
    if debug:
        print("evaluating myfunc for x = " + str(x) + " using exponent p = " + str(p))
    return x**p

myfunc(5)

myfunc(5, debug=True)

myfunc(p=3, debug=True, x=7)

f1 = lambda x: x**2
    
# is equivalent to 

def f2(x):
    return x**2

f1(2), f2(2)

# map is a built-in python function
map(lambda x: x**2, range(-3,4))

# in python 3 we can use `list(...)` to convert the iterator to an explicit list
list(map(lambda x: x**2, range(-3,4)))

elements = [-100, 21, 115, 0.34, 45, -80, 12, 120, 73, -1]

%load solutions/functions.py

def apply(l, fun):
    new_l = []
    for el in l:
        new_l.append(fun(el))
    return new_l

apply(elements, lambda x: abs(x))


import re  # Regular expression functionality of Python is placed in a separate module 're'

string = 'Hello, class! This is a testing string that contains a word CAT'
pattern = r'CAT'
match = re.search(pattern, string)
if match:
    print 'found', match.group()
else:
    print 'not found'

string = 'Hello, class! This is a testing string that contains a word caT'
pat = r'[cC][aA][tT]'
print 'found', re.search(pat, string).group()

# Special characters: . ^ $ * + ? { } [ ] \ | ( )
string = 'Hello, class! This is a testing string that contains a word CAR'
pat = 'CA.'
print 'found', re.search(pat, string).group()

string = 'Hello, class! This is a testing string that contains a word CAAAAAAAAAAAT'
pat = 'CA*T'
print 'found', re.search(pat, string).group()

string = 'Hello, class! This is a testing string that contains a word CAAT'
pat = 'CA+T'
print 'found', re.search(pat, string).group()

pat = re.compile(r'CA+T')
print 'found', pat.search(string).group()

# Yet another example
line = "Cats are smarter than dogs"

matchObj = re.match( r'(.*) are (.*?) .*', line)

if matchObj:
   print "matchObj.group() : ", matchObj.group()
   print "matchObj.group(1) : ", matchObj.group(1)
   print "matchObj.group(2) : ", matchObj.group(2)
else:
   print "No match!!"

dir(pat)

pat.findall?

# A piece of text from "KAUST Highlights of 2013" article
text = """
This past year saw members of KAUST faculty and leadership being awarded major international awards.
At the beginning of the year, Prof. Jean Frechet, KAUST Vice President for Research, was awarded the 2013 Japan
Prize in recognition of his original and outstanding scientific achievements serving to promote peace and prosperity
for all mankind. Dr. Frechet and C. Grant Willson of the University of Texas at Austin were recognized for their achievement
in the development of chemically amplified resistant polymer materials for innovative semiconductor manufacturing processes.
Also appointed in the past year, Prof. Yves Gnanou, KAUST Dean of Physical Science and Engineering (PSE), was inducted into
the elite ranks of the French Ordre national de la Légion d'honneur (National Order of the Legion of Honor). He was
presented with the coveted Chevalier medal at a ceremony held in Paris on June 27, 2013. Established over two centuries
ago by Napoleon Bonaparte, the award recognizes its recipients' extraordinary contributions to France and French culture.
Prof. Gnanou previously served as Vice President of Academic Affairs and Research at École Polytechnique in Paris. Spanning
a third continent, the Desert Research Institute (DRI), in the US, presented Nina Fedoroff, Distinguished Professor of Bioscience
and Director of the KAUST Center for Desert Agriculture, with the 2013 Nevada Medal. The award acknowledges outstanding achievements
in science and engineering. The DRI President, Dr. Stephen Wells, said: "In only a few decades Prof. Fedoroff's research
has helped stimulate a revolution in biology."
"""
pat = re.compile(r'awards?')
pat.findall(text)

pat = re.compile(r'award[^\s,.!?:;]*')
pat.findall(text)

pat = re.compile(r'(award)([^\s,.!?:;]*)')
pat.findall(text)

# Taken from somewhere from the web
emails ="""
litke@talktalk.net
owarne000s@talk21.com
seo@webindustry.co.uk
w0lfspirit32@hotmail.co.uk
robert.douglas3@virgin.net
dan@webindustry.co.uk
sasha_aitken@mail.ru
brian@tweddle1966.freeserve.co.uk
asmileiscatching@hotmail.com
sashalws@aol.com
ebbygraham372@hotmail.com
chnelxx@hotmail.com
choudhury.esaa@hotmail.co.uk
girishvishwasjoshi@gmail.com
mark.clynch@ntlworld.com
ssladmin@eskdalesaddlery.co.uk
owarnes.t21@btinternet.com
mgrahamhaulage@aol.com
beccababes@dsl.pipex.com
victor-2k7@hotmail.co.uk
kellybomaholly@hotmail.com
sugar@caton9108.freeserve.co.uk
paulapowley@btinternet.com
owarnes@talk21.com
lesleygodwin1@hotmail.com
nicolawinter4@hotmail.com
diwasbhattarai@yahoo.com
james.hutchinson@aggregate.com
margaret.howroyd@hotmail.com
tina.wane@tiscali.co.uk
lizzy26259495@yahoo.com
kennyspence53@hotmail.com
pedrovieira1@gmail.com
versivul@mail.ru
booom2012@mail.ru sin_0.8@mail.ru
kaplya71@mail.ru smirnova-s-s@mail.ru
325jm@mail.ru rasmyrik@mail.ru
tanya_tyurnina@mail.ru fedorova2006@inbox.ru
veniaminm77@mail.ru dimon_gushin@mail.ru
anna_shevchenko@list.ru belexovagalina@mail.ru
engelgardt_ledi_elena_01.11.77@mail.ru
kolzhanov92@mail.ru digital1q@mail.ru
"""

%load solutions/regular.py

pat = re.compile("([\w.-_]+)@([\w.-]+\.[a-z]+)")
email_list = pat.findall(emails)
print email_list[:3]
print "# of emails in the list is", len(email_list)


raise Exception("description of the error")

try:
    print("test")
    # generate an error: the variable test is not defined
    print(test)
except:
    print("Caught an expection")

try:
    print("test")
    # generate an error: the variable test is not defined
    print(test)
except Exception as e:
    print("Caught an exception:" + str(e))

os.makedirs('mydir')

os.makedirs('mydir') # This will raise error because the directory already exist

%load solutions/exeptions.py

def ensure_dir(d):
    import os, errno
    try:
        os.makedirs(d)
    #except OSError as exc:
    except Exception as exc:
        if exc.errno == errno.EEXIST:
            pass
        else: raise

ensure_dir('mydir')