CSC 110 Lab Week 9

Changing a data file

In this lab session you are going to read two data files, that share a column in common (id). First you need to create a dictionary with the .csv (comma separated values) file, with the unique ids as keys and names as values. Then you will read the tab separated value, which contains a the id and a city name, and you will create an output file that contains three values separate by comma in each line: the unique id is the first value, the second value is the name associated with the unique id (use the dictionary to retrieve the name based on the unique id), and the third value is the name of the city associated with each id.

Name your Python script add_column.py.

Files you will need:

• .csv file with ids and names (to create your dictionary with)
• .txt file that you will use to create your output file

Your output file that you are to write is the name of the .txt file preceded by the string "output_". For example, if the .txt file is called "cities.txt" the output file your script will create should be called "output_cities.txt"

Test cases

id_names = read_ids("ids_and_names.csv")
print(id_names)

{'166': 'Sylvia Phillis', '339': 'Carina Roxanna', '440': 'Monday Devon', 
 '393': 'Milford Elaine', '869': 'Garnet Guillermo', '471': 'Cassandra Ignacia', 
 '197': 'Murray Tomás', '489': 'Jacinta Layla', '799': 'Verity Mathew', 
 '251': 'Terance Mar', '259': 'Patrocinia Malcom', '464': 'Valentín Ximena', 
 '707': 'Bridgette Tiburcio', '356': 'Osborne Otilia', '406': 'Otilia Delano', 
 '123': 'Eneida Brennan', '332': 'Zackary Trenton', '743': 'Florencio Clotilde', 
 '176': 'Ariel Tamara', '546': 'Miranda Pamelia', '830': 'Fiona Garey', 
 '145': 'Verity Modesto', '585': 'Marvel Terrell', '479': 'Clarence Damon', 
 '801': 'Linden Herbert', '915': 'January Sunday', '598': 'Guadalupe Margaret',
 '538': 'Apolinar Olive', '789': 'Lisandro Agatha', '139': 'Mayra Sampson', 
 '261': 'Omar Demetria', '626': 'Hugh Laraine', '216': 'Kip Delfina', 
 '229': 'Godofredo Dutch', '983': 'Bevan Jarod', '604': 'Ellery Luján', 
 '357': 'Paulina Valorie', '120': 'Milford Lamar', '805': 'Fern Valeria', 
 '567': 'Mildred Paula', '665': 'Bernabé Mercy', '613': 'Ely Lindsay', 
 '838': 'Una Kerry', '951': 'Misti Valerio', '703': 'Nikole Norman', 
 '242': 'Melanie Edith', '810': 'Arlen Libertad', '722': 'Nola Virginia', 
 '204': 'Ward Brice', '649': 'Cristopher Xavier'}

Then, for the following function call:

add_name_column("ids_and_city.txt", id_names)

A file named "output_ids_and_city.txt" should be created with the following contents:

120,Milford Lamar,Ajo
123,Eneida Brennan,Avondale
139,Mayra Sampson,Avondale
145,Verity Modesto,Casa
166,Sylvia Phillis,Chandler
176,Ariel Tamara,Clifton
197,Murray Tomás,Douglas
204,Ward Brice,Avondale
216,Kip Delfina,Avondale
229,Godofredo Dutch,Avondale
242,Melanie Edith,Avondale
251,Terance Mar,Avondale
259,Patrocinia Malcom,Kingman
261,Omar Demetria,Tucson
332,Zackary Trenton,Mesa
339,Carina Roxanna,Nogales
356,Osborne Otilia,Nogales
357,Paulina Valorie,Phoenix
393,Milford Elaine,Prescott
406,Otilia Delano,Scottsdale
440,Monday Devon,Phoenix
464,Valentín Ximena,Tempe
471,Cassandra Ignacia,Phoenix
479,Clarence Damon,Tucson
489,Jacinta Layla,Tucson
538,Apolinar Olive,Tucson
546,Miranda Pamelia,Tucson
567,Mildred Paula,Yuma

There should be a line break at the end of every line, including the very last line that contains the three values.