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Builtin Objects and Methods

• A method is a subroutine (also called a function or procedure) that can be called to perform a computation or other action.
  1. Standalone Functions
     
     1. abs(n)      Return the absolute value of the number n.
     2. bool(v)    Convert the values v to boolean (bool object): 0, 0.0, "", and None to False; everything else to True.  
     3. chr(n)      Return the character that has the ASCII code n.
     4. float(v)   Convert a value v to a floating point number (float object).
     5. input(s)   Return a line typed in from the keyboard.  s is the prompt telling the user what to enter.
     6. int(v)      Convert a value v, which is a string or numeric value, to an integer (int object).
     7. len(obj)   Return the length of a string or list.
     8. list(obj)  Convert obj into a list. For example list("abc") returns ['a', 'b', 'c']. Also, list(range(1, 4)) returns [1, 2, 3].
     9. max(v1, v2, v2)    Return the maximum value of v1, v2, v3. The number of arguments is arbitrary.
     10. max(lst)   Return the maximum value of the list lst.
     11. min(v1, v2, v3)    Return the minimum value of v1, v2, v3. The number of arguments is arbitrary.
     12. min(lst)   Return the minimum value of the list lst.
     13. open(filename, mode)    Return a file object that accesses the file with specified filename and mode.
         Mode can be one of the strings "r": read, "w": write, "rb": read binary, "wb": write binary, "a": append.
     14. ord(c)      Return the ASCII code of the c, which is a string (str object) of length 1.
     15. range(end)    Return a range object with values [0, 1, ... , end - 2, end - 1]
     16. range(start, end)    Return a range object with values [start, start + 1, ... , end - 2, end - 1]
     17. range(start, end, step)     Return a range object with values [start, start + step, start + 2 * step, ... ]. The largest value of the returned range is less than end.
     18. repr(obj)  Return a technical string representation of the object obj, for use by developers.
     19. round(x, n)   Return the floating point value x rounded to n digits after the decimal point. If n is omitted, it defaults to zero
     20. str(obj)     Return a user friendly string (str object) representation of the object obj, in a form suitable for end users.
     21. type(obj)    Return the datatype or class of the object obj.
     
     
  2. String Methods   s is an str variable whose value is a character string. [ ] means optional parameter.
     
     1. s.capitalize( )  Return the string s with the first character capitalized if it is a letter.
     2. s.center(width[, fillchar='\n'])     Center s in a string of width.  Use fillchar to fill in the regions before and after s.
     3. s.count(sub)       Return the number of non-overlapping occurrences of the substring sub in s.
     4. s.endswith(suffix)   Return True if s ends with suffix, otherwise return False.
     5. s.find(sub)        Return the index of the first occurrence of sub within s. If sub is not found in s, return -1.
     6. s.format(args)  Return the data in args formatted according to the format string s.
     7. s.join(lst)        Join the list of strings lst using the seperator string s to form a single string
     8. s.lower( )          Return s with all letters, if any, converted to lower case all non-letters are unchanged.
     9. s.ljust(width[, fillchar='\n'])    Return s left justified in a string of length width. Fill with fillchar characters to the right.
     10. s.lstrip(char="\s\n\t")    Return a copy of the string with leading characters removed. chars is a string specifying the set of characters to be removed.
     11. s.rjust(width[, fillchar='\n'])    Return s right justified in a string of length width. Fill with fillchar characters to the left.
     12. s.rfind(sub)      Return the index of the last occurrence of sub within s. If sub is not found in s, return -1.
     13. s.rstrip(char="\s\n\t")    Return a copy of the string with trailing characters removed. chars is a string specifying the set of characters to be removed.
     14. s.replace(old, new[, count])     Return a copy of s with all occurrences of substring old replaced by new. If the optional argument count is given, only the first count occurrences are replaced.
     15. s.strip(chars="\s\n\t")    Return a copy of the string with leading and trailing characters removed. chars is a string specifying the set of characters to be removed.
     16. s.split(sep)     Return a list of the fields in a delimited string, where sep indicates the delimiter. A common delimiter is a comma, for example fields = s.split(',').
     17. s.startswith(suffix)   Return True if s begins with prefix, otherwise return False.
     18. s.swapcase( )   Return a copy of the string with uppercase characters converted to lowercase and vice versa.
     19. s.upper( )         Return s with all letters, if any, converted to upper case.
     
     
  3. List Methods   a is a list variable whose value is a list, also called an array. [ ] means optional parameter.
     
     1. a.append( )   Append an item to the end of the list.
     2. a.clear( )     Remove all items from the list. The resulting list looks like this: [ ].
     3. a.count(x)     Return the number of times x appears in the list.  If x is not found in the list, an error is raised.
     4. a.insert(i, x)   Insert an item x at position i. The first argument i is the index of the element before which to insert, so a.insert(0, x) inserts at the front of the list, and a.insert(len(a), x) is equivalent to a.append(x).
     5. len(a)     Return the number of items in the list.
     6. a.pop([x])     Remove the item at the given position in the list, and return it. If no index is specified, a.pop( ) removes and returns the last item in the list.
     7. a.remove(x)    Remove the first item from the list whose value is x. An error is raised if there is no such item.
     8. a.reverse( )  Reverse the items of the list in place.
  
  
• Dictionary Methods   d is a dict variable whose value is a dictionary object. [ ] means optional parameter.
  
  1. d[key]   Return the value in d with key key. If key is not in d, raise an error.
  2. d[key] = value   Set d[key] to value.
  3. key in d   Return True if d has a key key, else return False.
  4. d.clear( )   Remove all items from the dictionary.
  5. d.get(key)   Return the value for key if key is in d. If key is not in d, raise an error. This is the same as d[key].
  6. a.items( )   Return a new view of the items ((key,value) pairs) in d. This view is dynamic because it changes if the dictionary changes. Use the list method to change the view into a list, which is not dynamically tied to d.
  7. a.keys( )   Return a new view of the keys in d. This view is dynamic because it changes if the dictionary changes. Use the list method to change the view into a list, which is not dynamically tied to d.
  8. d.pop(key)   If key is in the dictionary, remove it and return its value. If key is not in d, an error is raised.
  9. a.values( )   Return a new view of the values in d. This view is dynamic because it changes if the dictionary changes. Use the list method to change the view into a list, which is not dynamically tied to d.