Diamond in Python
Given a letter, print a diamond starting with 'A' with the supplied letter at the widest point.
exercism fetch python diamond
The diamond kata takes as its input a letter, and outputs it in a diamond shape. Given a letter, it prints a diamond starting with 'A', with the supplied letter at the widest point.
- The first row contains one 'A'.
- The last row contains one 'A'.
- All rows, except the first and last, have exactly two identical letters.
- All rows have as many trailing spaces as leading spaces. (This might be 0).
- The diamond is horizontally symmetric.
- The diamond is vertically symmetric.
- The diamond has a square shape (width equals height).
- The letters form a diamond shape.
- The top half has the letters in ascending order.
- The bottom half has the letters in descending order.
- The four corners (containing the spaces) are triangles.
In the following examples, spaces are indicated by
Diamond for letter 'A':
Diamond for letter 'C':
Diamond for letter 'E':
····A···· ···B·B··· ··C···C·· ·D·····D· E·······E ·D·····D· ··C···C·· ···B·B··· ····A····
Sometimes it is necessary to raise an exception. When you do this, you should include a meaningful error message to indicate what the source of the error is. This makes your code more readable and helps significantly with debugging. Not every exercise will require you to raise an exception, but for those that do, the tests will only pass if you include a message.
To raise a message with an exception, just write it as an argument to the exception type. For example, instead of
raise Exception, you should write:
raise Exception("Meaningful message indicating the source of the error")
Running the tests
To run the tests, run the appropriate command below (why they are different):
- Python 2.7:
- Python 3.3+:
Alternatively, you can tell Python to run the pytest module (allowing the same command to be used regardless of Python version):
python -m pytest diamond_test.py
-v: enable verbose output
-x: stop running tests on first failure
--ff: run failures from previous test before running other test cases
For other options, see
python -m pytest -h
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exercism debug and looking for the line that starts with
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Submitting Incomplete Solutions
It's possible to submit an incomplete solution so you can see how others have completed the exercise.