Data Structures & Conditionals

• When using the equals sign operator, = is an assignment operator, while == is a relational operator.
• The OR operator returns TRUE if either condition is TRUE, else it will return FALSE.
• The AND operator only returns TRUE if both conditions if TRUE, else it will return FALSE.
• Any non-zero number in Python is interpreted as TRUE.
• IF statements are structured with a header followed by an indented body. This structure is called a block.
• There are two types of loops:

  • For loops
  • While loops
• Input the correct keywords:

  
  

  for char in "alpha":

  print(char)
• A FOR loop iterates over a set range of intervals whereas a WHILE loop iterates only as long as some condition is TRUE.
• There are two ways of controlling loops:

  • BREAK
  • CONTINUE
• BREAK exits the loop body immediately.
• CONTINUE skips ahead to the next iteration in a loop.
• A list is a python data structure that contains a sequential collection of zero or more Python data objects.
• Lists are mutable, meaning that values of an item in the list are modifiable.
• The IN operator asks whether an item is in a sequence.
• Tuples are immutable, meaning that values of an item in the list are unable to be modified.
• A tuple is an ordered sequence of values of any data type.
• Using tuples enable functions to return more than one value.
• Strings are usually indicated with single or double quotation marks around it.
• In order to concatenate two strings, we use the + operator to combine the two strings together.
• In order to repeat a string, the * operator is used to repeat the string by the number of times inputted.
• Indexing a string or a list is done by using square brackets and the value's index. E.g. schools [ 0 ] to locate the first school.
• Slicing a string or a list is done by using square brackets with a colon splitting the lower bound and upper bound. E.g. schools [ 0:5 ] to extract the first 5 schools.
• When slicing, the lower bound is inclusive while the upper bound is exclusive.
• Format specifiers allows control of the fill character, alignment, sign, width, precision, and type of data when it's substituted for the replacement field.
• The format of a specifer is <width>.<precision><type> , where width specifies the number of letters/digits allowed, precision is the number of decimal places, and type indicates the data type.
• A dictionary contains a key that is mapped to a value, also known as a key-value pair/item.
• A list is an ordered sequence of objects, whereas a dictionary is an unordered set.
• A dictionary key must be:

  • Unique within the dictionary
  • Immutable