025-weather/docs/dictionary.md

Domain Dictionary: Weather Data (Day 25)

Metadata

Key	Value
ID	DICT-001
CrossReference	BC-001, SA-001
Language	en
Domain	it

Version History

Date	Status	Author	Reviewer	Change	Commit
2026-10-13	Accepted	Jens Tirsvad Nielsen	AI as stand-in for S01	Initial version, reviewed in RC-003 (Go)	165e91a

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Purpose and Scope

Maps each Product Owner (PO) term to its professional information technology (IT) term. PO language: en (domain it), from the registry's Languages section. The PO terms are the words of the day-25 lectures as the planning documents use them; the IT terms are the names in the code. The dictionary exists so that the planning documents use one word for one thing and so that S02 can find the lectures' names in the code.

Dictionary

PO term	Language	IT term	Definition	Used as PO term in	Used as IT term in
CSV file	en	weather_data.csv	The text file with one line per day and the values day, temp and condition separated by commas.	BC, SA, PP, MIL	PY
header row	en	first row of the file	The first line of the CSV file, which names the columns and is not data.	BC, PP, MIL	PY
row	en	row	The values of one day.	BC, SA, PP, MIL	PY
column	en	Series	The values of one name, for example temp, from every row.	BC, SA, PP, MIL	PY
table	en	DataFrame	The whole data of the file, as rows and columns, like a sheet in a spreadsheet.	BC, SA, PP, MIL	PY
temperature	en	temp	The temperature of a day in degrees Celsius, a whole number.	BC, SA, PP, MIL	PY
condition	en	condition	The weather of a day as a word, for example Sunny.	BC, SA, PP, MIL	PY
read with csv	en	csv.reader	Getting the rows of the CSV file into the program with Python's built-in csv library.	BC, SA, PP, MIL	PY
read with pandas	en	pandas.read_csv	Getting the table of the CSV file into the program with one call of the pandas library.	BC, SA, PP, MIL	PY
dictionary	en	DataFrame.to_dict()	Names mapped to values; the table is turned into one, and a table can also be made from one.	BC, PP, MIL	PY
list	en	Series.to_list()	The values of a column in order.	BC, PP, MIL	PY
average	en	average_temp	The sum of the temperatures divided by their number.	BC, SA, PP, MIL	PY
mean	en	Series.mean()	The average that pandas computes for a column, used to check the average that is computed by hand.	BC, PP, MIL	PY
maximum	en	Series.max()	The largest temperature of the column.	BC, PP, MIL	PY
select	en	data[data.day == "Monday"]	Getting the rows for which a condition holds.	BC, PP, MIL	PY
Fahrenheit	en	temp * 9 / 5 + 32	The temperature converted from Celsius to the Fahrenheit scale.	BC, PP, MIL	PY
export	en	DataFrame.to_csv	Writing a table to a CSV file.	BC, SA, PP, MIL	PY
screenshot	en	docs/images/weather-run.png	The picture of the program running in a terminal that the README and the wiki show.	BC, SA, PP, MIL	none

Rules

• The Business Case, Stakeholder Analysis, Project Plan and milestones use the PO term; the source code and its tests use the IT term.
• One IT term per PO term and one PO term per IT term; no synonyms.
• The planning documents use British spelling; identifiers follow the lectures and the libraries.
• A code identifier written in backticks in a planning document is an IT term and is allowed there.
• "Step" is not a PO term of the program. In the planning documents it means a step of the project (a task, a milestone).

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