Xlsx
Excel file processing. USE WHEN xlsx, Excel, spreadsheet. SkillSearch('xlsx') for docs.
>_
Quick Installnpxskills add danielmiessler/personal_ai_infrastructure--skill XlsxInstructions
Loading…
Tags & Topics
aiaugmentationproductivityhumans
Excel file processing. USE WHEN xlsx, Excel, spreadsheet. SkillSearch('xlsx') for docs.
npxskills add danielmiessler/personal_ai_infrastructure--skill XlsxLoading…
Before starting any task with this skill, load complete PAI context:
read ~/.claude/skills/CORE/SKILL.md
This provides access to:
This sub-skill activates when the user's request involves Excel spreadsheets (.xlsx, .xlsm, .csv, .tsv).
Creation Workflow (openpyxl):
Editing Workflow (openpyxl):
load_workbook() to preserve existing formatting and formulasData Analysis Workflow (pandas):
Financial Modeling Workflow:
Recalculation Workflow:
recalc.py scriptUnless otherwise stated by the user or existing template
A user may ask you to create, edit, or analyze the contents of an .xlsx file. You have different tools and workflows available for different tasks.
LibreOffice Required for Formula Recalculation: You can assume LibreOffice is installed for recalculating formula values using the recalc.py script. The script automatically configures LibreOffice on first run
For data analysis, visualization, and basic operations, use pandas which provides powerful data manipulation capabilities:
import pandas as pd
# Read Excel
df = pd.read_excel('file.xlsx') # Default: first sheet
all_sheets = pd.read_excel('file.xlsx', sheet_name=None) # All sheets as dict
# Analyze
df.head() # Preview data
df.info() # Column info
df.describe() # Statistics
# Write Excel
df.to_excel('output.xlsx', index=False)
Always use Excel formulas instead of calculating values in Python and hardcoding them. This ensures the spreadsheet remains dynamic and updateable.
# Bad: Calculating in Python and hardcoding result
total = df['Sales'].sum()
sheet['B10'] = total # Hardcodes 5000
# Bad: Computing growth rate in Python
growth = (df.iloc[-1]['Revenue'] - df.iloc[0]['Revenue']) / df.iloc[0]['Revenue']
sheet['C5'] = growth # Hardcodes 0.15
# Bad: Python calculation for average
avg = sum(values) / len(values)
sheet['D20'] = avg # Hardcodes 42.5
# Good: Let Excel calculate the sum
sheet['B10'] = '=SUM(B2:B9)'
# Good: Growth rate as Excel formula
sheet['C5'] = '=(C4-C2)/C2'
# Good: Average using Excel function
sheet['D20'] = '=AVERAGE(D2:D19)'
This applies to ALL calculations - totals, percentages, ratios, differences, etc. The spreadsheet should be able to recalculate when source data changes.
python recalc.py output.xlsx
status is errors_found, check error_summary for specific error types and locations#REF!: Invalid cell references#DIV/0!: Division by zero#VALUE!: Wrong data type in formula# Using openpyxl for formulas and formatting
from openpyxl import Workbook
from openpyxl.styles import Font, PatternFill, Alignment
wb = Workbook()
sheet = wb.active
# Add data
sheet['A1'] = 'Hello'
sheet['B1'] = 'World'
sheet.append(['Row', 'of', 'data'])
# Add formula
sheet['B2'] = '=SUM(A1:A10)'
# Formatting
sheet['A1'].font = Font(bold=True, color='FF0000')
sheet['A1'].fill = PatternFill('solid', start_color='FFFF00')
sheet['A1'].alignment = Alignment(horizontal='center')
# Column width
sheet.column_dimensions['A'].width = 20
wb.save('output.xlsx')
# Using openpyxl to preserve formulas and formatting
from openpyxl import load_workbook
# Load existing file
wb = load_workbook('existing.xlsx')
sheet = wb.active # or wb['SheetName'] for specific sheet
# Working with multiple sheets
for sheet_name in wb.sheetnames:
sheet = wb[sheet_name]
print(f"Sheet: {sheet_name}")
# Modify cells
sheet['A1'] = 'New Value'
sheet.insert_rows(2) # Insert row at position 2
sheet.delete_cols(3) # Delete column 3
# Add new sheet
new_sheet = wb.create_sheet('NewSheet')
new_sheet['A1'] = 'Data'
wb.save('modified.xlsx')
Excel files created or modified by openpyxl contain formulas as strings but not calculated values. Use the provided recalc.py script to recalculate formulas:
python recalc.py <excel_file> [timeout_seconds]
Example:
python recalc.py output.xlsx 30
The script:
Quick checks to ensure formulas work correctly:
pd.notna()/ in formulas (#DIV/0!)The script returns JSON with error details:
{
"status": "success", // or "errors_found"
"total_errors": 0, // Total error count
"total_formulas": 42, // Number of formulas in file
"error_summary": { // Only present if errors found
"#REF!": {
"count": 2,
"locations": ["Sheet1!B5", "Sheet1!C10"]
}
}
}
data_only=True to read calculated values: load_workbook('file.xlsx', data_only=True)data_only=True and saved, formulas are replaced with values and permanently lostread_only=True for reading or write_only=True for writingpd.read_excel('file.xlsx', dtype={'id': str})pd.read_excel('file.xlsx', usecols=['A', 'C', 'E'])pd.read_excel('file.xlsx', parse_dates=['date_column'])IMPORTANT: When generating Python code for Excel operations:
For Excel files themselves:
Example 1: Build a financial model
User: "Create a revenue projection model for the next 5 years"
→ Creates workbook with assumptions sheet + projections
→ Uses Excel formulas (=SUM, growth rates) not hardcoded values
→ Applies color coding (blue inputs, black formulas), runs recalc.py
Example 2: Analyze data from Excel file
User: "What are the top 10 customers by revenue in this spreadsheet?"
→ Reads Excel with pandas
→ Groups, sorts, and filters data
→ Returns summary with statistics
Example 3: Update existing spreadsheet
User: "Add a new column with profit margin calculations"
→ Loads workbook preserving existing formulas
→ Adds new column with margin formula referencing existing cells
→ Saves and recalculates to verify no errors
#NAME?: Unrecognized formula name
Create or update AgentSkills. Use when designing, structuring, or packaging skills with scripts, references, and assets.
Create or update AgentSkills. Use when designing, structuring, or packaging skills with scripts, references, and assets.
Set up and use 1Password CLI (op). Use when installing the CLI, enabling desktop app integration, signing in (single or multi-account), or reading/injecting/running secrets via op.
CLI to manage emails via IMAP/SMTP. Use `himalaya` to list, read, write, reply, forward, search, and organize emails from the terminal. Supports multiple accounts and message composition with MML (MIME Meta Language).
Create or update AgentSkills. Use when designing, structuring, or packaging skills with scripts, references, and assets.
Create or update AgentSkills. Use when designing, structuring, or packaging skills with scripts, references, and assets.
Set up and use 1Password CLI (op). Use when installing the CLI, enabling desktop app integration, signing in (single or multi-account), or reading/injecting/running secrets via op.
CLI to manage emails via IMAP/SMTP. Use `himalaya` to list, read, write, reply, forward, search, and organize emails from the terminal. Supports multiple accounts and message composition with MML (MIME Meta Language).