MNMXT-bgol (Find Minimum & Maximum Number in a Boundary)

Command Type: AutoLISP routine (works in AutoCAD, BricsCAD, ZWCAD and most AutoLISP-compatible CAD platforms)
Developed by: BGol Community, bgol.in

Inspired by the general concept of boundary-scoped min/max text-value finder utilities used in survey/CAD drafting. This is an original, independently written routine, new file name, new command name, new source code, created so the CAD community has a free, editable, open-source alternative.

Overview

MNMX scans all numeric TEXT entities located inside a selected polyline boundary, identifies the minimum and maximum numeric values among them, and marks those two specific text entities with a fitted circle, filling a gap AutoCAD's native FIND command leaves, since FIND can only locate a value you already know, not tell you which of many text values is smallest or largest.

How to Use

1. Load MNMXT-bgol.lsp into your CAD session (drag-and-drop the file onto the drawing window, or use the APPLOAD command).
2. Type MNMX at the command line and press Enter.
3. Select a closed polyline boundary (e.g. a parcel or grid outline).
4. Every numeric TEXT entity whose insertion point falls inside that boundary is scanned. The minimum-value text is circled in blue and the maximum-value text is circled in red, both on layer BGOL-MNMX. The count of text found, and the minimum/maximum values, are reported at the command line.

Why Use It

• Fills a Native Gap, AutoCAD's FIND command can only locate a known value, not determine which of many is smallest or largest; this routine provides that missing capability.
• Spatially Scoped, uses a polyline boundary to scope the search, useful for finding the min/max within a specific area (e.g. one parcel or one grid section) rather than the whole drawing.
• Time Savings, instantly identifies extreme values instead of manually scanning and comparing every text value by eye.

Where to Use It

• Identifying the highest and lowest elevation points within a specific survey boundary or grid area.
• Any QA or design-review task needing the extreme (min/max) values within a defined region of a drawing quickly identified and marked.
• Earthwork or terrain analysis where knowing the highest/lowest spot levels within a boundary is a key first step.

Notes

• The boundary must be a LWPOLYLINE or POLYLINE; other entity types are rejected with a message.
• Point-in-boundary testing uses a standard crossing-number (point-in-polygon) algorithm against the boundary's vertex list.
• Non-numeric text inside the boundary is still scanned (parsed as 0), keep the boundary limited to genuinely numeric labels for reliable results.
• Source code is fully open, feel free to study, modify, and redistribute it under the same open, free-for-all spirit.

Credits

Developed and shared for the CAD community by BGol Community. Website: https://bgol.in/ Free and open-source, use it, modify it, share it, for personal or commercial work alike.