Add analysis function

ref-test/app/tools/data.py

@@ -1,4 +1,4 @@
-from ..models import Dataset
+from ..models import Dataset, Test
 from ..tools.logs import write
 
 from flask import current_app as app
@@ -7,6 +7,8 @@ from flask.helpers import abort, flash, redirect, url_for
 import json
 from pathlib import Path
 from random import shuffle
+from statistics import mean, median, stdev
+from typing import Union
 from functools import wraps
 
 def load(filename:str):
@@ -85,3 +87,62 @@ def check_dataset_exists(function):
             return redirect(url_for('admin._questions'))
         return function(*args, **kwargs)
     return wrapper
+
+def check_test_exists(function):
+    @wraps(function)
+    def wrapper(*args, **kwargs):
+        try: tests = Test.query.all()
+        except Exception as exception:
+            write('system.log', f'Database error when checking existing datasets: {exception}')
+            return abort(500)
+        if not tests:
+            flash('There are no exams configured. Please create an exam first.', 'error')
+            return redirect(url_for('admin._tests'))
+        return function(*args, **kwargs)
+    return wrapper
+
+def analyse(subject:Union[Dataset,Test]) -> dict:
+    output = {
+        'answers': {},
+        'entries': 0,
+        'grades': {
+            'merit': 0,
+            'pass': 0,
+            'fail': 0
+        },
+        'scores': {
+            'mean': 0,
+            'median': 0,
+            'stdev': 0
+        }
+    }
+    scores_raw = []
+    dataset = subject if isinstance(subject, Dataset) else subject.dataset
+    if isinstance(subject, Test):
+        for entry in subject.entries:
+            if entry.answers:
+                for question, answer in entry.answers.items():
+                    if int(question) not in output['answers']: output['answers'][int(question)] = {}
+                    if int(answer) not in output['answers'][int(question)]: output['answers'][int(question)][int(answer)] = 0
+                    output['answers'][int(question)][int(answer)] += 1
+            if entry.result:
+                output['entries'] += 1
+                output['grades'][entry.result['grade']] += 1
+                scores_raw.append(int(entry.result['score']))        
+    else:
+        for test in subject.tests:
+            output['entries'] += len(test.entries)
+            for entry in test.entries:
+                if entry.answers:
+                    for question, answer in entry.answers.items():
+                        if int(question) not in output['answers']: output['answers'][int(question)] = {}
+                        if int(answer) not in output['answers'][int(question)]: output['answers'][int(question)][int(answer)] = 0
+                        output['answers'][int(question)][int(answer)] += 1
+                if entry.result:
+                    output['entries'] += 1
+                    output['grades'][entry.result['grade']] += 1
+                    scores_raw.append(entry.result['score'])
+    output['scores']['mean'] = mean(scores_raw)
+    output['scores']['median'] = median(scores_raw)
+    output['scores']['stdev'] = stdev(scores_raw, output['scores']['mean']) if len(scores_raw) > 1 else None
+    return output