Suggestions for didec
The following packages have something in common with the package didec. The packages are ordered in decreasing similarity.
- basicarith: Macros for typesetting basic arithmetic
 - fp: Fixed point arithmetic
 - bxcalc: Extend the functionality of the calc package
 - bigintcalc: Integer calculations on very large numbers
 - intcalc: Expandable arithmetic operations with integers
 - bnumexpr: Extends ε-TeX’s \numexpr...\relax construct to big integers
 - zugferd: ZUGFeRD and Faktur-X invoicing using LaTeX
 - invoice: Generate invoices
 - longdivision: Typesets long division
 - calc: Simple arithmetic in LaTeX commands
 - qrbill: Create QR bills using LaTeX
 - realcalc: Macros for real arithmetic calculations
 - xint: Expandable arbitrary precision floating point and integer operations
 - zeckendorf: Knuth Fibonacci multiplication, Zeckendorf and Bergman representations of big integers
 - cvss: Compute and display CVSS base scores
 - numerica: Numerically evaluate mathematical expressions in LaTeX form
 - linearregression: Calculate and display linear regressions
 - pgfmath-xfp: Define pgfmath functions using xfp
 - randintlist: Creating random integer number lists, with repeating and sorting options
 - luacomplex: Operations on complex numbers inside LaTeX documents using Lua
 - simpleinvoice: Easy typesetting of invoices
 - invoice2: Intelligent invoices with LaTeX3
 - invoice-class: Produces a standard US invoice from a CSV file
 - minifp: Fixed-point real computations to 8 decimals
 - fltpoint: Simple floating point arithmetic
 - xlop: Calculates and displays arithmetic operations
 - factura: Typeset and calculate invoices according to Venezuelan law
 - isodoc: A LaTeX class for typesetting letters and invoices
 - randomwalk: Random walks using TikZ
 - pascaltriangle: Draw beautiful Pascal (Yanghui) triangles
 - numerica-plus: Iteration and recurrence relations: finding fixed points, zeros and extrema of functions