How to Get the Array Size in Pythonby Amber Viescas
Python, unlike other languages, does not implement a normal "length()" or "size()" method to read the size of an array -- e.g., "array.length()." Instead, it implements the len() method, which takes the array itself as a parameter. This method is identical between normal arrays, which are declared with "array.array(character)"; lists that are defined by square brackets ""; and tuples, which are defined by parentheses. Special object types, such as strings and trees, also implement this method.
Locate the variable name for your array. For instance, if it was declared in a line "arr = [1, 2, 3];" the variable name would be "arr." Arrays can also be declared as "array.array('i')" for an array of integers.
Reference the array's size as len(arr). Python interprets this as calling the method arr.__(len)__, which is a special internal method, implemented by most classes that have a length, that returns the array size.
Insert the reference into your code to access the array's size.
- "arr.__len__()" is also accepted by Python, but it is harder to remember.
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