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exercism fetch haskell matrix

Matrix

Given a string representing a matrix of numbers, return the rows and columns of that matrix.

So given a string with embedded newlines like:

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2
3
9 8 7
5 3 2
6 6 7

representing this matrix:

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2
3
4
5
    0  1  2
  |---------
0 | 9  8  7
1 | 5  3  2
2 | 6  6  7

your code should be able to spit out:

The rows for our example matrix:

And its columns:

Hints

To complete this exercise, you need to create the data type Matrix, with Eq and Show instances, and implement the following functions:

You will find a dummy data declaration and type signatures already in place, but it is up to you to define the functions and create a meaningful data type, newtype or type synonym.

No validation of input is required. Let it fail if the matrix is not rectangular, invalid chars are encountered, etc.

shape is (rows, cols)

Getting Started

For installation and learning resources, refer to the exercism help page.

Running the tests

To run the test suite, execute the following command:

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stack test

If you get an error message like this...

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No .cabal file found in directory

You are probably running an old stack version and need to upgrade it.

Otherwise, if you get an error message like this...

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No compiler found, expected minor version match with...
Try running "stack setup" to install the correct GHC...

Just do as it says and it will download and install the correct compiler version:

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stack setup

Running GHCi

If you want to play with your solution in GHCi, just run the command:

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stack ghci

Feedback, Issues, Pull Requests

The exercism/haskell repository on GitHub is the home for all of the Haskell exercises.

If you have feedback about an exercise, or want to help implementing a new one, head over there and create an issue. We'll do our best to help you!

Source

Warmup to the saddle-points warmup. http://jumpstartlab.com

Submitting Incomplete Solutions

It's possible to submit an incomplete solution so you can see how others have completed the exercise.