- added plot

.gitignore

 .idea/
 token.txt
+api/plot.svg

api/api.py

 import flask
 from flask import request, jsonify
 import sqlite3
+import matplotlib.pyplot as plt
+import numpy as np
 
 app = flask.Flask(__name__)
 app.config["DEBUG"] = True
@@ -67,4 +69,34 @@ def api_filter():
 
     return jsonify(results)
 
+
+@app.route('/api/v1/resources/books/plot', methods=['GET'])
+def book_plot():
+    db = sqlite3.connect('books.db')
+    db.row_factory = dict_factory
+    cur = db.cursor()
+    books = cur.execute('SELECT * FROM books;').fetchall()
+
+    seq = np.array([len(book['first_sentence']) for book in books])
+    pub = np.array([book['published'] for book in books])
+
+    plt.figure()
+
+    # add pionts
+    plt.scatter(pub, seq)
+
+    # add linear kurve
+    fac, off = np.polyfit(pub, seq, 1)
+    plt.plot(pub, fac * pub + off)
+
+    # add labels
+    plt.xlabel("date of publication")
+    plt.ylabel("length of first sentence in cahrs")
+
+    # create and open svg
+    plt.savefig("plot.svg")
+    svg = open("plot.svg").read()
+
+    return flask.Response(svg, mimetype='image/svg+xml')
+
 app.run()
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