Chapter 17 - Concept Summary¶
Chapter 17 included the following concepts from computing.
- List - A list holds items in order. An example of a list is
[1, 2, 3]. - Index - The index is the position of the item in a list or string. In Python the first item is at index 0.
- Out of Range Error - An out of range error will occur if you try to access an item in a list and give it an invalid index. The first item in a list is at index 0 and the last is at one less than the length.
- Parameter - A parameter is input to a procedure or function that is specified when you define the procedure or function. This is also called a formal parameter. The parameter will be assigned a value when the procedure or function is called.
- Substring - A substring is part of a string. You can use the slice operator in Python to get a substring.
Summary of Python Keywords and Functions¶
- Find - The
source.find(target)function returns the position of the target string in the source string if it is there or -1 if it is not. - Split - The
splitfunction returns a list of strings separated by a specified character. For example, ifmessage = "Nora, Jones, 15"thenmessage.split(",")would return['Nora', 'Jones', '15']. - Slice - The statement
source[pos]returns the character at that position in the string. This uses an index to get the character from the string at that index. The statementsource[start:end]returns the characters from start to one before end. It uses two indices the start index (inclusive) and the end index (exclusive) to return a substring of the string from the start character to one before the end character.