Generator

Chord steps per member of a drifting sequence, with the factorisation rebuilt every 4

One function in the reuse library, called 3 times across 3 essays. Below: what it draws at its defaults, what it draws at every value an essay asks for, the 8 claims it put to the test while drawing them, and where it stands against the rule this site is named for.

At its defaults it draws chord steps per member of a drifting sequence, with the factorisation rebuilt every 4. Each point is one member of a continuation, warm-started from the previous member's answer and solved with a factorisation that is between zero and 3 members old. The lower series is the same sequence with a fresh factorisation at every member, which costs 6 to 5 steps throughout. The kept run costs 6 steps on a fresh factor and 12 at its worst, for 5 factorisations against 20.

staleness-trail is one function in lib/figures/reuse.js — reuse — what a kept factorisation or preconditioner is worth, and for how long. Everything below came out of it during this build, at arguments taken from the essays rather than invented for this page. A figure here is the figure a reader meets in an essay, and if the generator changes, this page changes with it.

At its defaults

Drawn even though every essay passes arguments — which on this site is every essay, at 100% of placements since the standard pass. A default nothing exercises is a trap for the next essay to call this with none, and this is the page where a default that has drifted from the figures around it becomes visible.

Chord steps per member of a drifting sequence, with the factorisation rebuilt every 4Each point is one member of a continuation, warm-started from the previous member's answer and solved with a factorisation that is between zero and 3 members old. The lower series is the same sequence with a fresh factorisation at every member, which costs 6 to 5 steps throughout. The kept run costs 6 steps on a fresh factor and 12 at its worst, for 5 factorisations against 20.03691215182103691215member of the sequencechord steps to reach the tolerancea fresh factorisation each memberthe ringed points are the refactorisationsrebuilt every 4factorisations5chord steps160worst member's steps12multiplications1.2·10⁷with a fresh factor each time1.8·10⁷a factor is cheapest the member it was built forand dearest the member before it is replaced

Each point is one member of a continuation, warm-started from the previous member's answer and solved with a factorisation that is between zero and 3 members old. The lower series is the same sequence with a fresh factorisation at every member, which costs 6 to 5 steps throughout. The kept run costs 6 steps on a fresh factor and 12 at its worst, for 5 factorisations against 20.

refresh: 4

The arguments are the ones A factorisation kept past its date passes. A value nobody placed would be a picture no essay asked for and no claim was ever checked against.

Chord steps per member of a drifting sequence, with the factorisation rebuilt every 4Each point is one member of a continuation, warm-started from the previous member's answer and solved with a factorisation that is between zero and 3 members old. The lower series is the same sequence with a fresh factorisation at every member, which costs 6 to 5 steps throughout. The kept run costs 6 steps on a fresh factor and 12 at its worst, for 5 factorisations against 20.03691215182103691215member of the sequencechord steps to reach the tolerancea fresh factorisation each memberthe ringed points are the refactorisationsrebuilt every 4factorisations5chord steps160worst member's steps12multiplications1.2·10⁷with a fresh factor each time1.8·10⁷a factor is cheapest the member it was built forand dearest the member before it is replaced

Each point is one member of a continuation, warm-started from the previous member's answer and solved with a factorisation that is between zero and 3 members old. The lower series is the same sequence with a fresh factorisation at every member, which costs 6 to 5 steps throughout. The kept run costs 6 steps on a fresh factor and 12 at its worst, for 5 factorisations against 20.

refresh: 6

The arguments are the ones The penalty for keeping it is a ratio passes. A value nobody placed would be a picture no essay asked for and no claim was ever checked against.

Chord steps per member of a drifting sequence, with the factorisation rebuilt every 6Each point is one member of a continuation, warm-started from the previous member's answer and solved with a factorisation that is between zero and 5 members old. The lower series is the same sequence with a fresh factorisation at every member, which costs 6 to 5 steps throughout. The kept run costs 6 steps on a fresh factor and 20 at its worst, for 4 factorisations against 20.03691215182104812162024member of the sequencechord steps to reach the tolerancea fresh factorisation each memberthe ringed points are the refactorisationsrebuilt every 6factorisations4chord steps202worst member's steps20multiplications1.4·10⁷with a fresh factor each time1.8·10⁷a factor is cheapest the member it was built forand dearest the member before it is replaced

Each point is one member of a continuation, warm-started from the previous member's answer and solved with a factorisation that is between zero and 5 members old. The lower series is the same sequence with a fresh factorisation at every member, which costs 6 to 5 steps throughout. The kept run costs 6 steps on a fresh factor and 20 at its worst, for 4 factorisations against 20.

What it checked while drawing

Every figure above checked its own claims on the way to being drawn, and a claim that failed would have stopped the picture rather than shipped a wrong one. Those checks used to leave no trace at all: a passing one returned true and the only evidence the figure had checked anything was that nothing crashed. The list below is what they actually said, collected by running this generator with an observer installed — not a description of what it is believed to check.

8 distinct claims across 3 sets of arguments, grouped below by shape — because most of them are one sentence with a different number in it, and how many separate times that sentence was put to the test is the informative part.

a conditioning the SPD construction can hold

a factor kept for several members costs more at the end of its life than at the start

a refactorisation rule of one kind or the other

a refresh period inside the sweep

a size the dense factorisations are affordable at

and refactorising at every member is a sequence that converges throughout

matmul shapes agree

the sequence gets far enough to show the shape

Against the rule

The rule does not apply to it. It factorises nothing, so there is no residual it could be withholding. That is worth stating rather than leaving blank: a site that reported the rule as satisfied by every generator would be counting mostly generators the rule never reached.

Across the library: the rule bites on 217 of 397 generators — 199 print a residual and 18 are exempt with a published reason; 180 factorise nothing. Read from lib/residual-rule.js, which is the same body the gate enforces from, and the gate's last check fails the build if this page and it disagree about any generator.

Where it is called

Changing this generator changes every figure on this list. That is what makes the list worth publishing rather than keeping in a check script.

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