On Wed, Apr 12, 2023 at 11:33 PM Michael Wong <> wrote:
Hi all, SG19 Machine Learning meeting will focus on Graph. We still want to drive graph and stats to completion. Are there any other suggested topics? Thank you.

Michael Wong is inviting
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1. Opening and introductions

The ISO Code of conduct:

IEC Code of Conduct:

ISO patent policy.

The WG21 Practices and Procedures and Code of Conduct:

1.1 Roll call of participants
Phil Ratzloff, Andrew Lumsdaine, Chris Ryan.. Nathan Owens. Oliver Rosten, Richard Dosselmann, Sam Obeng, Scott McMillan, Michael Wong, Rene Rivera

1.2 Adopt agenda

1.3 Approve minutes from previous meeting, and approve publishing
 previously approved minutes to

1.4 Action items from previous meetings

2. Main issues (125 min)

2.1 General logistics

Meeting plan, focus on one paper per meeting but does not preclude other
paper updates:

CPPCON minutes:

Apr 13: Graph
May 11: Stats
June 15: Varna F2F (cancelled)
July 13: Matrix
Aug 10: Graph
Sep 14: Stats
Oct 12: Matrix
Nov 9: Graph

ISO meeting status

future C++ Std meetings

2.2 Paper reviews

2.2.1: ML topics Graph Proposal Phil Ratsloff et al

Latest paper:

Here’s a link to the paper (different than the previous paper reviewed).
There are some additional updates I’m planning on making before the meeting.

aim for Kona
Graph algorithm
adaptors with cpo
goal for edge list: very useful utility class, lots of graph i/o is done with edges

bipartite graphs are extremely useful (e.g. imdb) 

is list collection confusing? its arbitrary based on implementation, yes confusing
edge_list is a list, set, map, forward_list
has the current paper in Latex. You'll need to generate the paper

Algorithms follow standard ranges, separated into 3 tiers
T 2, 3 are paper for the future

 Is there a reason we have minimum spanning tree algorithms but not minimum spanning arborecence algorithms?
like MST but for directed graphs: yes can be in both directions, may be just a specia;ization

Should we parallelize, accelerate
yes, have a placeholder, execution_policy, allows symmetrical interface if parameter is always there
some like dijkstra's is sequential, so parallel version is delta-stepping
E.g. chu-liu/edmonds'
DFS is inherently sequential




Array copy semantics:
array copy-semantics paper P1997 "Relaxing Restrictions on Arrays",

Stats feedback:

on Simple Statistical Functions (p1708r4): Contracts, Exceptions and
Special cases Johan Lundberg Reinforcement Learning Larry Lewis Jorge Silva

Reinforcement Learning proposal: Differential Calculus: Stats paper

<> More
Stats Functions Richard Dosselmann, Michael Wong
Current github

Stats review Richard Dosselman et al

Feedback from Johan Lundberg and Oleksandr Korval

P1708R3: Math proposal for Machine Learning: 3rd review

PXXXX: combinatorics: 1st Review

*> above is the stats paper that was reviewed in Prague*
*> Review Jolanta Polish feedback.*

More stats paper:
5.2.1 mode accumulator class has ability to compare
agree to not use long name so just percentile (no of_sorted)
5.2.2 covariance accumulator class templates
use typedef because it is a mouthful
common_type_t would reduce worthiness

preconditions of variance needing 2 values, whereas mean requires 1, another one requires 3
decided to not doing a lot of check - what kind of checks? exceptions? optional? expected? at BSI, choose expected
if you violate preconditins, its UB
due to empty ranges
can we say the operator parenthesis been called twice? it is using outside r, so the length is less then length of W, same length as x, y

checking or not: user has to done the right thing, e.e. binary_search
here you just count the number of invocations

A public implementation is available at ... 
Choose an open source license | Choose a License Matrix paper

2.2.3 any other proposal for reviews?

2.3 Other Papers and proposals

P1416R1: SG19 - Linear Algebra for Data Science and Machine Learning

P1415: Machine Learning Layered list

2.2.2 SG14 Linear Algebra progress:
Different layers of proposal

2.5 Future F2F meetings:

2.6 future C++ Standard meetings:


3. Any other business

New reflector

Old Reflector!newtopic/sg19

Code and proposal Staging area

4. Review

4.1 Review and approve resolutions and issues [e.g., changes to SG's
working draft]

4.2 Review action items (5 min)

5. Closing process

5.1 Establish next agenda

5.2 Future meeting
Apr 13: Graph
May 11: Stats
June 15: Varna F2F (cancelled)
July 13: Matrix
Aug 10: Graph
Sep 14: Stats
Oct 12: Matrix
Nov 9: Graph
Dec 14: Stats