6.4. Exercises¶

The following sample file called studentdata.txt contains one line for each student in an imaginary class. The student’s name is the first thing on each line, followed by some exam scores. The number of scores might be different for each student.
```
joe 10 15 20 30 40
bill 23 16 19 22
sue 8 22 17 14 32 17 24 21 2 9 11 17
grace 12 28 21 45 26 10
john 14 32 25 16 89
```
Using the text file studentdata.txt write a program that creates a new data table that contains the names of students that have more than six quiz scores.
with open("studentdata.txt", "r") as f: lines = [line for line in f] words = [line.split() for line in lines] new_data = [row[0] for row in words if len(row[1:]) > 6] new_data

Using the text file studentdata.txt (shown in exercise 1) write a program that calculates the average grade for each student, and print out the student’s name along with their average grade. Use list comprehensions and lambda functions while paying attention to the levels of abstraction.

Using the text file studentdata.txt (shown in exercise 1) write a program that creates a new data table that contains the students’ names along with the minimum and maximum score for each student.

with open("studentdata.txt", "r") as f: table = [line.split() for line in f] convert_scores = lambda row: [int(num) for num in row[1:]] process_row = lambda row: (row[0], max(convert_scores(row)), min(convert_scores(row))) new_table = [process_row(row) for row in table] new_table

SeanLahman.com provides a database of baseball statistics. Download, unzip and extract the file titled Batting.csv.

Write each of the following functions and apply them to the related task. Each function should consist of a lambda expression and list comprehension. You will need to use the following function in your program.
```
def read_csv(filename, delimiter=','):
    from csv import reader
    with open(filename) as infile:
        inreader = reader(infile)
        table = [row for row in reader]
    return table
```
1. Write a function that takes a year and table of batting data as input and returns the average number of runs scored in that year. Call this function average_runs_year.
2. Write a function takes a list of years and a table of batting data and returns of list of tuples of the form (year, averages_runs). Call this function average_runs_years Use a list comprehension and the function from the last step.
3. Write a program that includes the above functions and reads Batting.csv and compute the average number of runs for the following years: 1900, 1910, ..., 2000, 2010. Assume that the Batting.csv file is the same directory as your program.

Determine the time complexity of each of the functions the last question (read_csv, average_runs_year, average_runs_years).

Download, unzip and extract the file titled Salaries.csv and AllstarFull.csv from seanlahman.com .

Write a program that computes the average salary of all players in the all star game in 2010.

Download, unzip and extract the file titled Salaries.csv and Batting.csv. from seanlahman.com

Write a program that computes the current salary of the player with the highest batting average in the last 5 years.

Download, unzip and extract the file titled Master.csv and BattingPost.csv. from seanlahman.com

Write a program that computes the total runs scored in the post season by all players from Minnesota (all time).

Next Section - 7. Functional List Processing