A Programming Approach to the CS Principles Data Task

Transcription

1 A Programming Approach to the CS Principles Data Task (from The Beauty and Joy of Computing team) UC Berkeley Sr Lecturer SOE Dan Garcia bjc.berkeley.edu

2 Broadening Participation in HS CS! New Course: Computer Science : Principles ú Engaging, accessible, inspiring, rigorous ú Focused on the fundamental concepts of computing (Computational Thinking) ú An impetus for college curriculum reform ú Available nationwide, Fall 2016-Spring 2017 SINGLE SOURCE OF NATIONAL LEVERAGE! csprinciples.org 2 / 25 A Programming Approach to the CS Principles Data Task

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4 CSP Curricular Framework: Data 3. Data and Information 1. People use computer programs to process information to gain insight and knowledge. 1. Use computers to process information, find patterns, and test hypotheses about digitally processed information to gain insight and knowledge 2. Collaborate when processing information to gain insight and knowledge 3. Explain the insight and knowledge gained from digitally processed data by using appropriate visualizations, notation, and precise language 2. Computing facilitates exploration and the discovery of connections in information. 1. Extract information from data to discover and explain connections, patterns, or trends (Students are not expected to know specific formulas or options available in spreadsheet or database software packages) 2. Use large data sets to explore and discover information and knowledge 3. There are trade-offs when representing information as digital data 1. Analyze how data representation, storage, security, and transmission of data involve computational manipulation of information 4 / 25 A Programming Approach to the CS Principles Data Task

5 UC Berkeley s BJC The Beauty and Joy of Computing UC Online AP CS Principles Grant Winner Pilot Pilot x3 Award Winner 2009Fa : 16 students (pilot) 2010Fa : 90 students 2011Sp : 90 students 2011Su : ~25 HS teachers in BJC Family! 2011Fa : 250 Students 2012Sp : 250 Students 2012Su : ~100 HS teachers online! 2012Fa : 250 Students & 60 UCB online pilot 2013Sp : 250 Students 2013Su: ~175 HS teachers in BJC Family! 2013Fa : 360 Students 2014Sp: 250 Students 2014Su: ~250 HS teachers (~10 faculty) in BJC Family bjc.berkeley.edu

6 Let s double all of your salaries! Write a function now! Input: list of salaries Output: new list of doubled salaries Go! (you can work in teams) 6 / 25 A Programming Approach to the CS Principles Data Task

7 First try using repeat block 7 / 25 A Programming Approach to the CS Principles Data Task

8 First try using repeat block yay! 8 / 25 A Programming Approach to the CS Principles Data Task

9 First try using for block 9 / 25 A Programming Approach to the CS Principles Data Task

10 First try using for block yay! 10 / 25 A Programming Approach to the CS Principles Data Task

11 First try using for each block 11 / 25 A Programming Approach to the CS Principles Data Task

12 First try using for each block yay! 12 / 25 A Programming Approach to the CS Principles Data Task

13 But can we do better? 13 / 25 A Programming Approach to the CS Principles Data Task

14 One line!! 14 / 25 A Programming Approach to the CS Principles Data Task

15 Why use functions? (review) The power of generalization! 15 / 25 A Programming Approach to the CS Principles Data Task

16 But how general can we be?? The power of generalization! 16 / 25 A Programming Approach to the CS Principles Data Task

17 Higher-Order Functions Functions as Data Useful HOFs (you can build your own!) ú map Reporter over List Report a new list, every element E of List becoming Reporter(E) ú keep items such that Predicate from List Report a new list, keeping only elements E of List if Predicate(E) ú combine with Reporter over List Combine all the elements of List with Reporter(E) This is also known as reduce Acronym example ú keep è map è combine 17 / 25 A Programming Approach to the CS Principles Data Task

18 combine with Reporter over List a b c d

19 HOFs are one of our Big Ideas! Functions as data is one of the two (programming) big ideas in this course It s a beautiful example of the abstraction of the list iteration details Google (and other companies) use this! ú They use map-reduce (Image Credit: Simply Scheme by Brian Harvey & Matt Wright) (Credit: Geekologie) 19 / 25 A Programming Approach to the CS Principles Data Task

20 Higher-Order Functions (HOFs) Useful HOFs (can also build your own!) ú map Reporter over List Report a new list, every element E of List becoming Reporter(E) ú keep items such that Predicate from List Report a new list, keeping only elements E of List if Predicate(E) ú combine with Reporter over List Combine all the elements of List with Reporter(E) This is also known as reduce bjc.berkeley.edu snap.berkeley.edu 20 / 25 A Programming Approach to the CS Principles Data Task

21 Big Data: 1880 baby names, let s do it Name Gender Number Mary F 7065 Anna F 2604 John M 9655 William M / 25 A Programming Approach to the CS Principles Data Task

22 Visualization Epic FAIL Fox News Graphic on the Obamacare Enrollment as of / 25 A Programming Approach to the CS Principles Data Task

23 Visualization Epic WIN (1869) Charles Joseph Minard, Napoleon s 1812 Russian Campaign 23 / 25 A Programming Approach to the CS Principles Data Task

24 youtu.be/jbksrlysojo Visualization Epic WIN (2009) 24 / 25 A Programming Approach to the CS Principles Data Task

25 Resources Snap: BJC: BJC Data Lecture slides ú %20Data/ BJC Lab Curriculum (Topic 14 Data Unit): ú GPS forensics activity ú Spam vs Ham detector An unusual episode : ú Usually done without computers; by providing raw data you can open up a computer-based task, however: 25 / 25 A Programming Approach to the CS Principles Data Task