Add matrix exercise (#761)

Author: tasxatzial

config.json

@@ -1141,6 +1141,17 @@
           "math"
         ]
       },
+      {
+        "slug": "matrix",
+        "name": "Matrix",
+        "uuid": "24ff1abf-c242-4054-ada4-19d6fd4f8c3c",
+        "practices": [],
+        "prerequisites": [
+          "strings",
+          "vectors"
+        ],
+        "difficulty": 4
+      },
       {
         "slug": "meetup",
         "name": "Meetup",

exercises/practice/matrix/.docs/instructions.md

@@ -0,0 +1,38 @@
+# Instructions
+
+Given a string representing a matrix of numbers, return the rows and columns of that matrix.
+
+So given a string with embedded newlines like:
+
+```text
+9 8 7
+5 3 2
+6 6 7
+```
+
+representing this matrix:
+
+```text
+    1  2  3
+  |---------
+1 | 9  8  7
+2 | 5  3  2
+3 | 6  6  7
+```
+
+your code should be able to spit out:
+
+- A list of the rows, reading each row left-to-right while moving top-to-bottom across the rows,
+- A list of the columns, reading each column top-to-bottom while moving from left-to-right.
+
+The rows for our example matrix:
+
+- 9, 8, 7
+- 5, 3, 2
+- 6, 6, 7
+
+And its columns:
+
+- 9, 5, 6
+- 8, 3, 6
+- 7, 2, 7

exercises/practice/matrix/.meta/config.json

@@ -0,0 +1,19 @@
+{
+  "authors": [
+    "tasxatzial"
+  ],
+  "files": {
+    "solution": [
+      "src/matrix.clj"
+    ],
+    "test": [
+      "test/matrix_test.clj"
+    ],
+    "example": [
+      ".meta/example.clj"
+    ]
+  },
+  "blurb": "Given a string representing a matrix of numbers, return the rows and columns of that matrix.",
+  "source": "Exercise by the JumpstartLab team for students at The Turing School of Software and Design.",
+  "source_url": "https://turing.edu"
+}

exercises/practice/matrix/.meta/example.clj

@@ -0,0 +1,17 @@
+(ns matrix
+  (:require [clojure.string :as str]))
+
+(defn get-row
+  "Returns the i-th row of the matrix s"
+  [s i]
+  (let [lines (str/split-lines s)
+        row (str/split (get lines (dec i)) #" ")]
+    (map #(Integer/parseInt %) row)))
+
+(defn get-column
+  "Returns the i-th column of the matrix s"
+  [s i]
+  (let [lines (str/split-lines s)
+        matrix (map #(str/split % #" ") lines)
+        column (map #(get % (dec i)) matrix)]
+    (map #(Integer/parseInt %) column)))

exercises/practice/matrix/.meta/generator.tpl

@@ -0,0 +1,13 @@
+(ns matrix-test
+  (:require [clojure.test :refer [deftest testing is]]
+            matrix))
+{{#test_cases.row}}
+(deftest get-row_test_{{idx}}
+  (testing {{string description}}
+    (is (= {{expected}} (matrix/get-row {{string input.string}} {{input.index}})))))
+{{/test_cases.row~}}
+{{#test_cases.column}}
+(deftest get-column_test_{{idx}}
+  (testing {{string description}}
+    (is (= {{expected}} (matrix/get-column {{string input.string}} {{input.index}})))))
+{{/test_cases.column~}}

exercises/practice/matrix/.meta/tests.toml

@@ -0,0 +1,34 @@
+# This is an auto-generated file.
+#
+# Regenerating this file via `configlet sync` will:
+# - Recreate every `description` key/value pair
+# - Recreate every `reimplements` key/value pair, where they exist in problem-specifications
+# - Remove any `include = true` key/value pair (an omitted `include` key implies inclusion)
+# - Preserve any other key/value pair
+#
+# As user-added comments (using the # character) will be removed when this file
+# is regenerated, comments can be added via a `comment` key.
+
+[ca733dab-9d85-4065-9ef6-a880a951dafd]
+description = "extract row from one number matrix"
+
+[5c93ec93-80e1-4268-9fc2-63bc7d23385c]
+description = "can extract row"
+
+[2f1aad89-ad0f-4bd2-9919-99a8bff0305a]
+description = "extract row where numbers have different widths"
+
+[68f7f6ba-57e2-4e87-82d0-ad09889b5204]
+description = "can extract row from non-square matrix with no corresponding column"
+
+[e8c74391-c93b-4aed-8bfe-f3c9beb89ebb]
+description = "extract column from one number matrix"
+
+[7136bdbd-b3dc-48c4-a10c-8230976d3727]
+description = "can extract column"
+
+[ad64f8d7-bba6-4182-8adf-0c14de3d0eca]
+description = "can extract column from non-square matrix with no corresponding row"
+
+[9eddfa5c-8474-440e-ae0a-f018c2a0dd89]
+description = "extract column where numbers have different widths"

exercises/practice/matrix/deps.edn

@@ -0,0 +1,6 @@
+{:aliases {:test {:extra-paths ["test"]
+                 :extra-deps {io.github.cognitect-labs/test-runner 
+                              {:git/url "https://github.com/cognitect-labs/test-runner.git"
+                               :sha "705ad25bbf0228b1c38d0244a36001c2987d7337"}}
+                 :main-opts ["-m" "cognitect.test-runner"]
+                 :exec-fn cognitect.test-runner.api/test}}}

exercises/practice/matrix/project.clj

@@ -0,0 +1,4 @@
+(defproject matrix "0.1.0-SNAPSHOT"
+  :description "matrix exercise."
+  :url "https://github.com/exercism/clojure/tree/main/exercises/practice/matrix"
+  :dependencies [[org.clojure/clojure "1.11.1"]])

exercises/practice/matrix/src/matrix.clj

@@ -0,0 +1,13 @@
+(ns matrix)
+
+(defn get-row
+  "Returns the i-th row of the matrix s"
+  [s i]
+  ;; function body
+  )
+
+(defn get-column
+  "Returns the i-th column of the matrix s"
+  [s i]
+  ;; function body
+  )

exercises/practice/matrix/test/matrix_test.clj

@@ -0,0 +1,35 @@
+(ns matrix-test
+  (:require [clojure.test :refer [deftest testing is]]
+            matrix))
+
+(deftest get-row_test_1
+  (testing "extract row from one number matrix"
+    (is (= [1] (matrix/get-row "1" 1)))))
+
+(deftest get-row_test_2
+  (testing "can extract row"
+    (is (= [3 4] (matrix/get-row "1 2\n3 4" 2)))))
+
+(deftest get-row_test_3
+  (testing "extract row where numbers have different widths"
+    (is (= [10 20] (matrix/get-row "1 2\n10 20" 2)))))
+
+(deftest get-row_test_4
+  (testing "can extract row from non-square matrix with no corresponding column"
+    (is (= [8 7 6] (matrix/get-row "1 2 3\n4 5 6\n7 8 9\n8 7 6" 4)))))
+
+(deftest get-column_test_1
+  (testing "extract column from one number matrix"
+    (is (= [1] (matrix/get-column "1" 1)))))
+
+(deftest get-column_test_2
+  (testing "can extract column"
+    (is (= [3 6 9] (matrix/get-column "1 2 3\n4 5 6\n7 8 9" 3)))))
+
+(deftest get-column_test_3
+  (testing "can extract column from non-square matrix with no corresponding row"
+    (is (= [4 8 6] (matrix/get-column "1 2 3 4\n5 6 7 8\n9 8 7 6" 4)))))
+
+(deftest get-column_test_4
+  (testing "extract column where numbers have different widths"
+    (is (= [1903 3 4] (matrix/get-column "89 1903 3\n18 3 1\n9 4 800" 2)))))