45 lines
1.9 KiB
Org Mode
45 lines
1.9 KiB
Org Mode
*** Python applying learnings from 1..6
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**** Lecture notes
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- Previous topics covered:
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- Printing
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- Formatting
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- Variables
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- Escape Sequences
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- Inputting text
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- Reading arguments / using argv
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- Reading files
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- Defining methods
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- Boolean logic
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- Branching using if/else/elif
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- Loops: for/while
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- Today we write a calculator that saves results in a file in python
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- How it works in general
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You read the input until you read a line that only contains a
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"q". Every input line consists of numbers separated by a
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space. For instance "4 5 9". You will need to .split() the
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input.
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- Steps
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- Create a python script named "calc.py"
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- It takes 1 command line argument (argv), which is the filename
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- We will store the calculations *and* results in this file
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- Create a method named "input_and_calculate_one_line"
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- It does not have any arguments
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- It reads one line via *input*
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- It splits the input (let's say "4 5 9" => [ "4", "5", "9") ])
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- It calculates the result (f.i. 4+5+9 = 18) and stores it in
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a variable (use *sum* over the *list*)
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- It returns a string of the format "4 + 5 + 9 = 18"
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- If the line only contains a "q" it return "" (an empty string)
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- Create a method named "editor" that takes a filename as an argument
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- It opens the file for writing
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- It uses input_and_calculate_one_line in a while loop
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- while the return result is not "", we append the string to
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the file
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- When the return result is "", the function exits
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*** State:
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input_and_calculate_one_line is complete, however it's probably a garbage implementation.
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Spent too much time on converting back and forth and getting the output right.
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Editor (file io) is not complete yet
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