Excel formula hell: =IF(A2=11,'Fund_A',IF(A2=12,'Fund_B',IF(A2=13... ENOUGH!

🎯 Replace Nested IF Statements with Python Functions

PANDAUDIT Team
10 min read

The Excel Monster That Haunts Us All

You need to classify fund codes. Your Excel formula looks like this:

=IF(A2=11,"Fund_A",
  IF(A2=12,"Fund_B",
    IF(A2=13,"Fund_C",
      IF(A2=14,"Fund_D",
        IF(A2=15,"Fund_E",
          IF(A2=16,"Fund_F",
            IF(A2=17,"Fund_G",
              IF(A2=18,"Fund_H","Unknown"))))))))

Count the parentheses. I dare you. 😵

Now imagine:

  • Your boss adds 3 new fund codes
  • You need to update this formula in 12 different workbooks
  • You accidentally delete one parenthesis
  • Excel crashes and you lose 30 minutes of work

Sound familiar? Let’s end this madness.


Why Nested IFs Are Terrible

🐛 Problem 1: Unreadable

=IF(A2=11,"Fund_A",IF(A2=12,"Fund_B",IF(A2=13,"Fund_C",IF(A2=14,"Fund_D",IF(A2=15,"Fund_E",IF(A2=16,"Fund_F",IF(A2=17,"Fund_G",IF(A2=18,"Fund_H","Unknown"))))))))

Try to read that in 6 months. Try to debug it. Try to explain it to a coworker.

💥 Problem 2: Fragile

One typo = broken formula. One extra/missing parenthesis = hours of debugging.

🐢 Problem 3: Slow to Update

Add a new fund code? You have to:

  1. Find all workbooks with this formula
  2. Edit each formula carefully
  3. Check you didn’t break anything
  4. Copy formula down entire columns
  5. Pray you didn’t miss any

📊 Problem 4: Excel Limits

Excel allows max 64 nested IFs. What if you have 65+ categories? You’re stuck.


The Python Solution: Dictionaries + Functions

Here’s the elegant, professional approach:

import pandas as pd

def classify_fund(code):
    """Map fund codes to fund names - clean and maintainable"""
    funds = {
        11: 'Fund_A',
        12: 'Fund_B', 
        13: 'Fund_C',
        14: 'Fund_D',
        15: 'Fund_E',
        16: 'Fund_F',
        17: 'Fund_G',
        18: 'Fund_H'
    }
    return funds.get(code, 'Unknown')  # Return 'Unknown' if code not found

# Apply to entire column instantly
df['Fund_Name'] = df['Fund_Code'].apply(classify_fund)

print("Done!")
print(df[['Fund_Code', 'Fund_Name']].head())

What Just Happened?

Let me break this down:

1️⃣ The Dictionary (Lookup Table)

funds = {
    11: 'Fund_A',
    12: 'Fund_B',
    # ...
}

This is like a VLOOKUP table, but built right into your code.

  • Key: The fund code (11, 12, 13, …)
  • Value: The fund name (‘Fund_A’, ‘Fund_B’, …)

2️⃣ The .get() Method

return funds.get(code, 'Unknown')

Translation: “Look up the code in the funds dictionary. If found, return the name. If not found, return ‘Unknown’.”

No IF statements. No nested logic. Just a simple lookup.

3️⃣ The .apply() Method

df['Fund_Name'] = df['Fund_Code'].apply(classify_fund)

Translation: “For every row in the Fund_Code column, run the classify_fund function and put the result in Fund_Name column.”


Real-World Example: Complete Fund Classification

Here’s a working example:

import pandas as pd

# Sample data
data = {
    'Account': ['1200-11-001', '1300-12-002', '1400-13-003', '1500-99-004'],
    'Fund_Code': [11, 12, 13, 99],
    'Amount': [5000, 3000, 2000, 1000]
}

df = pd.DataFrame(data)

print("BEFORE:")
print(df)

# Classification function
def classify_fund(code):
    """Map fund codes to fund names"""
    funds = {
        11: 'Fund_A',
        12: 'Fund_B',
        13: 'Fund_C',
        14: 'Fund_D',
        15: 'Fund_E',
        16: 'Fund_F',
        17: 'Fund_G',
        18: 'Fund_H'
    }
    return funds.get(code, 'Unknown')

# Apply classification
df['Fund_Name'] = df['Fund_Code'].apply(classify_fund)

print("\nAFTER:")
print(df)

# Summary by fund
print("\nSUMMARY:")
print(df.groupby('Fund_Name')['Amount'].sum())

Output:

BEFORE:
        Account  Fund_Code  Amount
0  1200-11-001         11    5000
1  1300-12-002         12    3000
2  1400-13-003         13    2000
3  1500-99-004         99    1000

AFTER:
        Account  Fund_Code  Amount Fund_Name
0  1200-11-001         11    5000    Fund_A
1  1300-12-002         12    3000    Fund_B
2  1400-13-003         13    2000    Fund_C
3  1500-99-004         99    1000   Unknown

SUMMARY:
Fund_Name
Fund_A     5000
Fund_B     3000
Fund_C     2000
Unknown    1000
Name: Amount, dtype: int64

Beautiful! 🎉


Advanced: Multi-Condition Classification

What if your classification needs multiple conditions? Still easy:

def classify_account(row):
    """
    Classify accounts based on multiple conditions:
    - Account number range
    - Fund code  
    - Amount threshold
    """
    account_num = int(row['Account'][:4])  # First 4 digits
    fund_code = row['Fund_Code']
    amount = row['Amount']
    
    # Revenue accounts (1000-1999)
    if 1000 <= account_num < 2000:
        if amount > 10000:
            return 'Major Revenue'
        else:
            return 'Minor Revenue'
    
    # Expense accounts (2000-2999)
    elif 2000 <= account_num < 3000:
        if fund_code in [11, 12, 13]:
            return 'Operating Expense'
        else:
            return 'Capital Expense'
    
    # Asset accounts (3000-3999)
    elif 3000 <= account_num < 4000:
        return 'Asset'
    
    # Liability accounts (4000-4999)
    elif 4000 <= account_num < 5000:
        return 'Liability'
    
    else:
        return 'Other'

# Apply to entire dataframe
df['Category'] = df.apply(classify_account, axis=1)

Try doing THAT with nested IFs in Excel! 😅


Bonus: Load Classifications from Excel

What if your mapping changes frequently? Store it in Excel and load it:

import pandas as pd

# Load mapping from Excel
mapping = pd.read_excel('fund_mappings.xlsx')
print("Mapping table:")
print(mapping)

# Convert to dictionary
fund_dict = dict(zip(mapping['Fund_Code'], mapping['Fund_Name']))

# Classification function (now uses the loaded mapping)
def classify_fund(code):
    return fund_dict.get(code, 'Unknown')

# Apply
df['Fund_Name'] = df['Fund_Code'].apply(classify_fund)

Your Excel file (fund_mappings.xlsx):

| Fund_Code | Fund_Name |
|-----------|----------|
| 11        | Fund_A   |
| 12        | Fund_B   |
| 13        | Fund_C   |
| ..        | ..       |

Now when your boss adds a new fund code, just update the Excel file. No code changes needed!


Comparison: Excel vs Python

Adding a New Category:

Excel:

=IF(A2=11,"Fund_A",IF(A2=12,"Fund_B",IF(A2=13,"Fund_C",IF(A2=14,"Fund_D",IF(A2=15,"Fund_E",IF(A2=16,"Fund_F",IF(A2=17,"Fund_G",IF(A2=18,"Fund_H",IF(A2=19,"Fund_I","Unknown")))))))))
         ↑ Find the right spot, add another IF, count all parentheses, pray

Python:

funds = {
    11: 'Fund_A',
    12: 'Fund_B',
    13: 'Fund_C',
    # ...
    18: 'Fund_H',
    19: 'Fund_I'  # ← Add one line. Done.
}

Performance:

Rows Excel Formula Python
1,000 Slow <1 sec
10,000 Very slow <1 sec
100,000 Crashes 2 sec

Maintainability:

Excel: 😱 Good luck
Python: 😊 Clear and obvious


Even More Advanced: Hierarchical Classification

Need nested classifications? Easy:

def get_budget_category(account_num):
    """Classify accounts into budget categories and subcategories"""
    
    categories = {
        # Format: (start, end): (category, subcategory)
        (1000, 1099): ('Revenue', 'Tax Revenue'),
        (1100, 1199): ('Revenue', 'Investment Income'),
        (1200, 1299): ('Revenue', 'Other Revenue'),
        (2000, 2099): ('Expense', 'Personnel'),
        (2100, 2199): ('Expense', 'Operations'),
        (2200, 2299): ('Expense', 'Capital'),
        (3000, 3999): ('Asset', 'Current Assets'),
        (4000, 4999): ('Liability', 'Current Liabilities'),
    }
    
    account_num = int(account_num[:4])  # First 4 digits
    
    for (start, end), (cat, subcat) in categories.items():
        if start <= account_num <= end:
            return cat, subcat
    
    return 'Unknown', 'Unknown'

# Apply and split into two columns
df[['Category', 'Subcategory']] = df['Account'].apply(
    lambda x: pd.Series(get_budget_category(x))
)

print(df[['Account', 'Category', 'Subcategory']])

Output:

     Account  Category       Subcategory
0  1050-001   Revenue       Tax Revenue
1  1150-002   Revenue  Investment Income
2  2050-003   Expense         Personnel
3  3050-004     Asset    Current Assets

Try It Yourself!

Quick Start:

import pandas as pd

# Your data
df = pd.read_excel('your_data.xlsx')

# Define your classification
def classify(code):
    mapping = {
        'A': 'Category 1',
        'B': 'Category 2',
        'C': 'Category 3',
        # Add your categories
    }
    return mapping.get(code, 'Unknown')

# Apply it
df['Category'] = df['Code'].apply(classify)

# Save results
df.to_excel('classified_data.xlsx', index=False)

Done! No nested IFs. No headaches.


The Bottom Line

What You Get:

  • Replace 8-level nested IFs with 10 lines of clean code
  • Add new categories in seconds
  • Handle unlimited classifications (not limited to 64)
  • Code that’s actually readable
  • Professional, maintainable solution

Time Saved:

  • Writing formula: 10 min → 3 min
  • Updating formula: 5 min → 10 seconds
  • Debugging formula: 15 min → 1 min

Sanity Points:

  • Excel: -100 (nested IF trauma)
  • Python: +100 (elegant solution)

What’s Next?

Now that you can classify data elegantly, check out:


Your Turn!

💬 What’s the worst nested IF formula you’ve seen?
Share in the comments—let’s see who has the most parentheses! 🏆

🤔 Need help converting your specific formula?
Post it below (remove sensitive data) and I’ll help you translate it to Python!


Tags: #Python #Pandas #Excel #Functions #BusinessLogic #Automation #DataMapping #FinancialAnalysis


Part of the “From Excel Hell to Python Heaven” series. Subscribe for more Excel-killing tips!

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