File size: 7,590 Bytes
b67668b
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
from __future__ import annotations

import re
from dataclasses import dataclass
from typing import Dict, List, Tuple, Optional

import pandas as pd
from dateutil import parser as dtparser
from rapidfuzz import process, fuzz

WORD_NUMS = {
    "zero": 0, "one": 1, "two": 2, "three": 3, "four": 4, "five": 5,
    "six": 6, "seven": 7, "eight": 8, "nine": 9, "ten": 10,
    "eleven": 11, "twelve": 12, "thirteen": 13, "fourteen": 14,
    "fifteen": 15, "sixteen": 16, "seventeen": 17, "eighteen": 18, "nineteen": 19,
    "twenty": 20, "thirty": 30, "forty": 40, "fifty": 50, "sixty": 60
}

DEPT_CANON = {
    "ai": "Artificial Intelligence",
    "artificial intelligence": "Artificial Intelligence",
    "ai/ml": "AI/ML",
    "ml": "Machine Learning",
    "machine learning": "Machine Learning",
    "data science": "Data Science",
    "datascience": "Data Science",
}

LOCATION_CANON = {
    "nyc": "New York",
    "new york": "New York",
    "san francisco": "San Francisco",
    "chicago": "Chicago",
    "seattle": "Seattle",
    "boston": "Boston",
}

EMAIL_RE = re.compile(r"^[A-Za-z0-9._%+\-]+@[A-Za-z0-9.\-]+\.[A-Za-z]{2,}$")

@dataclass
class CleaningReport:
    rows: int
    fixes: Dict[str, int]
    warnings: List[str]

def _clean_name(s: str) -> Optional[str]:
    if s is None or pd.isna(s):
        return None
    s = str(s).strip()
    s = re.sub(r"\s+", " ", s)
    s = " ".join([w.capitalize() for w in s.split()])
    return s if s else None

def _parse_word_number(s: str) -> Optional[int]:
    if s is None:
        return None
    t = str(s).strip().lower()
    if t == "":
        return None
    if re.fullmatch(r"\d+", t):
        return int(t)
    parts = re.split(r"[\s\-]+", t)
    total = 0
    matched = False
    for p in parts:
        if p in WORD_NUMS:
            total += WORD_NUMS[p]
            matched = True
        else:
            return None
    return total if matched else None

def _clean_email(s: str) -> Tuple[str, bool]:
    if s is None:
        return "unknown@unknown.com", True
    t = str(s).strip().lower()
    if t == "":
        return "unknown@unknown.com", True
    t = t.replace(" at ", "@").replace(" dot ", ".")
    t = t.replace("..", ".")
    t = re.sub(r"@{2,}", "@", t)
    if EMAIL_RE.match(t):
        return t, (t != str(s).strip().lower())
    if "@" in t and "." not in t.split("@", 1)[1]:
        return t, False
    return t, False

def _clean_salary(s: str) -> Tuple[Optional[float], bool]:
    if s is None:
        return None, False
    t = str(s).strip()
    if t == "" or t.lower() == "nan":
        return None, False
    t2 = re.sub(r"[,$]", "", t)
    t2 = re.sub(r"usd", "", t2, flags=re.I).strip()
    try:
        return float(t2), (t2 != t)
    except ValueError:
        return None, False

def _clean_date(s: str) -> Tuple[Optional[str], bool]:
    if s is None:
        return None, False
    t = str(s).strip()
    if t == "" or t.lower() == "nan":
        return None, False
    try:
        dt = dtparser.parse(t, dayfirst=False, fuzzy=True)
        iso = dt.date().isoformat()
        return iso, (iso != t)
    except Exception:
        return None, False

def _canon_from_map(value: str, mapping: Dict[str, str], threshold: int = 90) -> Tuple[str, bool]:
    raw = (value or "").strip()
    if raw == "":
        return raw, False
    key = raw.lower()
    if key in mapping:
        canon = mapping[key]
        return canon, canon != raw
    match = process.extractOne(key, mapping.keys(), scorer=fuzz.ratio)
    if match and match[1] >= threshold:
        canon = mapping[match[0]]
        return canon, canon != raw
    return raw, False

def clean_dataframe(df: pd.DataFrame) -> Tuple[pd.DataFrame, CleaningReport]:
    out = df.copy()
    fixes: Dict[str, int] = {}
    warnings: List[str] = []

    out.columns = [c.strip() for c in out.columns]
    col_map = {c.lower(): c for c in out.columns}

    name_col = col_map.get("name")
    age_col = col_map.get("age")
    email_col = col_map.get("email")
    salary_col = col_map.get("salary")
    join_col = col_map.get("join_date") or col_map.get("join date")
    dept_col = col_map.get("department")
    perf_col = col_map.get("performance_score") or col_map.get("performance score")
    loc_col = col_map.get("location")

    if name_col:
        before = out[name_col].astype(str).tolist()
        out[name_col] = out[name_col].apply(_clean_name)
        fixes["name_normalized"] = sum(b != a for b, a in zip(before, out[name_col].tolist()))

    if age_col:
        def clean_age(x):
            if x is None:
                return None
            t = str(x).strip().lower()
            if t == "":
                return None
            n = _parse_word_number(t)
            if n is not None:
                return n
            try:
                return int(float(t))
            except Exception:
                return None
        before = out[age_col].tolist()
        out[age_col] = out[age_col].apply(clean_age)
        fixes["age_parsed"] = sum(b != a for b, a in zip(before, out[age_col].tolist()))

    if email_col:
        before = out[email_col].tolist()
        new_vals, changed = [], 0
        for v in before:
            cleaned, did = _clean_email(v)
            if did:
                changed += 1
            new_vals.append(cleaned)
        out[email_col] = new_vals
        fixes["email_cleaned"] = changed
        invalid = [e for e in out[email_col].tolist() if not EMAIL_RE.match(e)]
        if invalid:
            warnings.append(f"{len(invalid)} email(s) still look invalid (e.g., '{invalid[0]}').")

    if salary_col:
        before = out[salary_col].tolist()
        vals, changed = [], 0
        for v in before:
            s2, did = _clean_salary(v)
            if did:
                changed += 1
            vals.append(s2)
        out[salary_col] = vals
        fixes["salary_cleaned"] = changed

    if join_col:
        before = out[join_col].tolist()
        vals, changed = [], 0
        for v in before:
            d2, did = _clean_date(v)
            if did:
                changed += 1
            vals.append(d2)
        out[join_col] = vals
        fixes["join_date_normalized"] = changed

    if dept_col:
        before = out[dept_col].astype(str).tolist()
        new, changed = [], 0
        for v in before:
            canon, did = _canon_from_map(v, DEPT_CANON, threshold=90)
            if did:
                changed += 1
            new.append(canon)
        out[dept_col] = new
        fixes["department_standardized"] = changed

    if loc_col:
        before = out[loc_col].astype(str).tolist()
        new, changed = [], 0
        for v in before:
            canon, did = _canon_from_map(v, LOCATION_CANON, threshold=88)
            if did:
                changed += 1
            new.append(canon)
        out[loc_col] = new
        fixes["location_standardized"] = changed

    if perf_col:
        before = out[perf_col].tolist()
        def clean_perf(x):
            if x is None:
                return None
            t = str(x).strip().lower()
            if t == "" or t == "nan":
                return None
            n = _parse_word_number(t)
            if n is not None:
                return float(n)
            try:
                return float(t)
            except Exception:
                return None
        out[perf_col] = out[perf_col].apply(clean_perf)
        fixes["performance_parsed"] = sum(b != a for b, a in zip(before, out[perf_col].tolist()))

    return out, CleaningReport(rows=len(out), fixes=fixes, warnings=warnings)