Algorithms For Dummies

 

   

  PART 1 

 Getting Started

Creating and Using Strings

Of all the data types, strings are the most easily understood by humans and not 

understood at all by computers. A string is simply any grouping of characters you 

place within double quotation marks. For example, 

myString = "Python is a 

great language."

 assigns a string of characters to 

myString

.

The main reason to use strings when working with algorithms is to provide user 

interaction — either as requests for input or as a means of making output easier 

to understand. You can also perform analysis of string data as part of working 

with algorithms, but the computer doesn’t actually require strings as part of its 

sequence of steps to obtain a solution to a problem. In fact, the computer doesn’t 

see letters at all. Every letter you use is represented by a number in memory. For 

example,  the  letter  A  is  actually  the  number  65.  To  see  this  for  yourself,  type 

ord("A") at the Python prompt and press Enter. You see 65 as output. You can 

convert any single letter to its numeric equivalent using the 

ord()

 command.

Operator

Description

== !=

Equality operators.

= %= /= //= -= += *= **=

Assignment operators.

is

is not

Identity operators.

in

not in

Membership operators.

not or and

Logical operators.