Verify and document FRFcoord multiple point input support

[Copilot]

The FRFcoord function already supports array inputs for batch coordinate conversion. This capability exists through pyproj >= 3.0.0's Transformer class, which natively handles array transformations.

Status

No code changes required. The issue has been resolved by the pyproj library update (version 3.0+), and the existing implementation properly leverages this capability.

Current Behavior

import numpy as np
from murgtools.utils import geoprocess as gp

# Single point - returns scalars
result = gp.FRFcoord(566.93, 515.11)
# result['xFRF'] is float

# Multiple points - returns arrays (no loop needed)
x_arr = np.array([100.0, 200.0, 300.0, 566.93])
y_arr = np.array([100.0, 200.0, 300.0, 515.11])
result = gp.FRFcoord(x_arr, y_arr)
# result['xFRF'] is ndarray with shape (4,)

# Performance: 85-378x faster than external loops

Array Support Coverage

All coordinate transformation functions support array inputs:

• FRFcoord() - universal converter
• FRF2ncsp(), ncsp2FRF() - FRF ↔ State Plane
• ncsp2LatLon(), LatLon2ncsp() - State Plane ↔ Lat/Lon
• LatLon2utm(), utm2LatLon() - Lat/Lon ↔ UTM
• utm2ncsp(), ncsp2utm() - UTM ↔ State Plane

Deliverables

• VERIFICATION_FRF_MULTIPLE_POINTS.md - Documentation with usage examples, performance comparisons, and technical details
• examples/demo_multiple_point_conversion.py - Interactive demonstration script showing all conversion modes

Original prompt

---

This section details on the original issue you should resolve

<issue_title>add capability to FRF coord to operate with multiple input points</issue_title>
<issue_description>currently FRF coord is limited to single point inputs thereby requiring looping outside of this function. This issue is focused on enhancing that capability. Desired input would go from a single point to an input array for p1, p2 variables.

</issue_description>

<agent_instructions>i think this was solved with most recent update to Transformer class in pyproj. confirm or fix </agent_instructions>

Comments on the Issue (you are @copilot in this section)

• Fixes add capability to FRF coord to operate with multiple input points #11

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[Copilot]

Pull request overview

This PR documents and demonstrates that the FRFcoord function and related coordinate transformation functions already support array inputs for batch coordinate conversion, a capability provided by pyproj >= 3.0.0. No code changes were needed.

Changes:

• Added comprehensive verification documentation (VERIFICATION_FRF_MULTIPLE_POINTS.md) explaining array support, usage examples, and technical details
• Added interactive demonstration script (demo_multiple_point_conversion.py) showing all conversion modes with performance comparisons

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
VERIFICATION_FRF_MULTIPLE_POINTS.md	Documents array input support verification, provides usage examples, and explains technical implementation details
examples/demo_multiple_point_conversion.py	Demonstrates single/array conversion modes across all coordinate systems with performance benchmarks

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