First part covering 3 topics, python numeric types, character string basics and sequences types. Source from John W. Shipman

1. Python 2
Basic Python Part 1
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2. Requirements
 Python editor:
 Spyder (Anaconda )
 Python version: 2.7 and above
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3. 1.0 Python numeric types
 Basic operation ( + , - , * , / )
To get the accurate
answer, write in a
decimal point.
Because number
without decimal
point is consider as
integer, a whole
number.
Two same function, but
different approach. Print
function will round-off
the nearest number.
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4. 1.1 Assignment statement
 Name can be attach to a value and the value will stay around for the rest of
conversational Python session.
 Python names must start with a letter or the underbar(_)character.
 Examples:
 How many seconds in 1 days?
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5.  General form of an assignments
 𝑛𝑎𝑚𝑒1 = 𝑛𝑎𝑚𝑒2 = ⋯ = 𝑒𝑥𝑝𝑟𝑒𝑠𝑠𝑖𝑜𝑛
It gives the same
output, since it
carries the same
expression.
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6. 2.0 Character String Basics
 In python you can choose to enclose strings either using single-quotes (‘…’)
or double-quotes (“……”)
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Print function
will output
the string
without the
quotes.

7.  Converting string, 𝑠𝑡𝑟 to integer, 𝑖𝑛𝑡 or vice-versa
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8.  Python has several escape sequences.
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If a line is not
finished,
python will
displays a
“….” prompt. Using print
function, will
gives the
exact output
in 3 lines.
It will read
directly the line
and output using
the special
escape character
n

9. 2.1 indexing strings
 To extract one or more characters from a string value, you need to know the
position. The diagram shows the position between characters, which its
starts before the first to the end of strings.
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10. 2.2 String methods
Method General expression Examples
center()
To center text
s.center(n)
.ljust() and .rjust()
Pad to length on left or
right
s.ljust(n)
s.rjust(n)
.strip(), .lstrip() and
.rstrip()
Remove leading and/or
trailing whitespace
s.strip()
s.lstrip()
s.rstrip()
count()
Search string s to see
how many times t occur
in string s
s.count(t)
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Many expression on strings are expressed as method. To call a method, we can use this syntax:
• expr.method(𝑎𝑟𝑔1, 𝑎𝑟𝑔2, … )
If length isn’t enough, it
will return the original
values.

11. Izyan Yasmin 2017
Method General expression Examples
.find() and r.find()
Locate string within a
longer string
s.find(t)
.startswith() and
.endswith()
To check if a string s
starts with a string t
s.startswith(t)
s.endswith(t)
.lower() and .upper()
Used to convert
uppercased characters to
lower and vice-versa
s.lower()
s.uppper()
.split()
Break field out of a
strings
s.split()

12. 2.3 String format method
 To combine string operations is to combine fixed text and variable values
into single string.
 General string of format operations:
 s.format(𝑝0, 𝑝1, … , 𝑘0 = 𝑒 𝑜, 𝑘1 = 𝑒1)
 Formatting of an item can be control using a format code of the form “{N:type}”, N is
number of arguments to the . 𝑓𝑜𝑟𝑚𝑎𝑡() method, and type specifies details of the
formatting.
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13. 3.0 Sequence types
 A sequence in Python represents an ordered set.
 str and unicode used to hold text, that is strings characters.
 list and tuple used for sequence of zero or more values of any type.
 Use list if the content of the sequence may change. Enclosed with square bracket “[…]”.
[𝑒𝑥𝑝𝑟1, 𝑒𝑥𝑝𝑟2, … . ]
 Use tuple if the contents may not change. Enclosed in parentheses “(….)”
(𝑒𝑥𝑝𝑟1, 𝑒𝑥𝑝𝑟2, … . )
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14. 3.1 Function and operators
Description Operators Example
Return numbers of elements
in a sequence s
len(s)
Return largest value in a
sequence s
max(s)
Return smallest value in
sequence s
min(s)
To test set of membership in
To concatenate two sequence
of the same type
+
To get a new sequence
containing n repetition of
elements of s
*
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15. 3.2 Indexing the position in a sequence
 Positions in a sequence refer to locations between the values, using an
expression s[i].
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Last line is an error because there is
nothing in position 12 in string fruits.

16. 3.3 Slicing sequences
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Types of slicing Descriptions Examples
S[B:E] Produces new sequences
S[B:] Get list on left hand-side
S[:E] Get list on right hand-side
S[B:E]=[]
del S[B:E]
Delete a slice from
sequences

17. 3.4 Sequence methods
 To find the positions of a value V, in a sequence S.
 S.index(V)
 Returns the number of elements S that are equal to V.
 S.count(V)
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18. 3.5 List Method
 For any instances L, the.append(V)method appends a new value to the
list
 Insert new value, V at an arbitrary position, P using this expression
L.insert(P,V)
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19.  Method L.remove(V) removes the first element of L that equals V, if
there is one. If no elements equal to V, method raises a ValueError
exception.
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20.  L.sort(), method sorts the elements of a list into ascending order.
 L.reverse(), which reverses the elements in place.
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21. 3.6 the range() function: creating arithmetic
progressions
 range(n), return a list containing an arithmetic progression.
 To generate a sequence [i, i+1, i+2, ..., n-1], use the form range(i, n)
 To generate an arithmetic progression with a difference d between successive
values, use the three-argument form range(i, n, d). The resulting sequence will be [i,
i+d, i+2*d, ...], and will stop before it reaches a value equal to n.
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22. 3.7 One value can have multiple names
 It is necessary to be careful when modifying mutable values such as list
because there may be more than one name bound to the value.
 𝑉1, 𝑉2 = … . . = 𝑒𝑥𝑝𝑟
 We can make a new list using a slice that selects all the elements of menu1.
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23. Reference
 http://infohost.nmt.edu/tcc/help/pubs/lang/pytut27/pytut27.pdf
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