Generator

One system, one tolerance, and 11 different amounts of work

One function in the race library, called 5 times across 1 essay. Below: what it draws at its defaults, what it draws at every value an essay asks for, the 5 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 one system, one tolerance, and 11 different amounts of work. Conjugate gradients on a 200 × 200 symmetric positive definite matrix with κ = 10⁴, stopped when the relative residual falls below 10⁻¹⁰, run at each of 13 partition counts. The only thing that differs between the runs is how many pieces the two global inner products were summed in — which on a real machine is the number of workers. Iteration counts run from 674 to 690, 11 of them distinct, a spread of 2.4% of the work. Every run converged and every answer is right to the accuracy asked for; the forward errors span 6.31·10⁻¹¹ to 1.08·10⁻¹⁰, a factor of 1.72. What differs is not a digit at the end of an answer — it is the bill, and it is an integer.

iteration-race is one function in lib/figures/race.js — what a reduction decides when the decision is discrete — a step count, a rank, and a test's tolerance. 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.

One system, one tolerance, and 11 different amounts of workConjugate gradients on a 200 × 200 symmetric positive definite matrix with κ = 10⁴, stopped when the relative residual falls below 10⁻¹⁰, run at each of 13 partition counts. The only thing that differs between the runs is how many pieces the two global inner products were summed in — which on a real machine is the number of workers. Iteration counts run from 674 to 690, 11 of them distinct, a spread of 2.4% of the work. Every run converged and every answer is right to the accuracy asked for; the forward errors span 6.31·10⁻¹¹ to 1.08·10⁻¹⁰, a factor of 1.72. What differs is not a digit at the end of an answer — it is the bill, and it is an integer.110¹670673676679682685688691694pieces the inner products were summed initerations to the tolerance674, the cheapest run690, the dearestthe same solve, pricedpartitionings run13distinct counts11spread, per cent2.4best forward error6.3·10⁻¹¹worst1.1·10⁻¹⁰one matrix, one toleranceand the cost is the machine's

Conjugate gradients on a 200 × 200 symmetric positive definite matrix with κ = 10⁴, stopped when the relative residual falls below 10⁻¹⁰, run at each of 13 partition counts. The only thing that differs between the runs is how many pieces the two global inner products were summed in — which on a real machine is the number of workers. Iteration counts run from 674 to 690, 11 of them distinct, a spread of 2.4% of the work. Every run converged and every answer is right to the accuracy asked for; the forward errors span 6.31·10⁻¹¹ to 1.08·10⁻¹⁰, a factor of 1.72. What differs is not a digit at the end of an answer — it is the bill, and it is an integer.

logKappa: 4

The arguments are the ones A stopping test is a race passes. A value nobody placed would be a picture no essay asked for and no claim was ever checked against.

One system, one tolerance, and 11 different amounts of workConjugate gradients on a 200 × 200 symmetric positive definite matrix with κ = 10⁴, stopped when the relative residual falls below 10⁻¹⁰, run at each of 13 partition counts. The only thing that differs between the runs is how many pieces the two global inner products were summed in — which on a real machine is the number of workers. Iteration counts run from 674 to 690, 11 of them distinct, a spread of 2.4% of the work. Every run converged and every answer is right to the accuracy asked for; the forward errors span 6.31·10⁻¹¹ to 1.08·10⁻¹⁰, a factor of 1.72. What differs is not a digit at the end of an answer — it is the bill, and it is an integer.110¹670673676679682685688691694pieces the inner products were summed initerations to the tolerance674, the cheapest run690, the dearestthe same solve, pricedpartitionings run13distinct counts11spread, per cent2.4best forward error6.3·10⁻¹¹worst1.1·10⁻¹⁰one matrix, one toleranceand the cost is the machine's

Conjugate gradients on a 200 × 200 symmetric positive definite matrix with κ = 10⁴, stopped when the relative residual falls below 10⁻¹⁰, run at each of 13 partition counts. The only thing that differs between the runs is how many pieces the two global inner products were summed in — which on a real machine is the number of workers. Iteration counts run from 674 to 690, 11 of them distinct, a spread of 2.4% of the work. Every run converged and every answer is right to the accuracy asked for; the forward errors span 6.31·10⁻¹¹ to 1.08·10⁻¹⁰, a factor of 1.72. What differs is not a digit at the end of an answer — it is the bill, and it is an integer.

logKappa: 2

The arguments are the ones A stopping test is a race passes. A value nobody placed would be a picture no essay asked for and no claim was ever checked against.

One system, one tolerance, and 2 different amounts of workConjugate gradients on a 200 × 200 symmetric positive definite matrix with κ = 100, stopped when the relative residual falls below 10⁻¹⁰, run at each of 13 partition counts. The only thing that differs between the runs is how many pieces the two global inner products were summed in — which on a real machine is the number of workers. Iteration counts run from 104 to 105, 2 of them distinct, a spread of 1.0% of the work. Every run converged and every answer is right to the accuracy asked for; the forward errors span 7.09·10⁻¹¹ to 8.48·10⁻¹¹, a factor of 1.19. What differs is not a digit at the end of an answer — it is the bill, and it is an integer.110¹100102104106108pieces the inner products were summed initerations to the tolerance104, the cheapest run105, the dearestthe same solve, pricedpartitionings run13distinct counts2spread, per cent0.96best forward error7.1·10⁻¹¹worst8.5·10⁻¹¹one matrix, one toleranceand the cost is the machine's

Conjugate gradients on a 200 × 200 symmetric positive definite matrix with κ = 100, stopped when the relative residual falls below 10⁻¹⁰, run at each of 13 partition counts. The only thing that differs between the runs is how many pieces the two global inner products were summed in — which on a real machine is the number of workers. Iteration counts run from 104 to 105, 2 of them distinct, a spread of 1.0% of the work. Every run converged and every answer is right to the accuracy asked for; the forward errors span 7.09·10⁻¹¹ to 8.48·10⁻¹¹, a factor of 1.19. What differs is not a digit at the end of an answer — it is the bill, and it is an integer.

logKappa: 3

The arguments are the ones A stopping test is a race passes. A value nobody placed would be a picture no essay asked for and no claim was ever checked against.

One system, one tolerance, and 4 different amounts of workConjugate gradients on a 200 × 200 symmetric positive definite matrix with κ = 1000, stopped when the relative residual falls below 10⁻¹⁰, run at each of 13 partition counts. The only thing that differs between the runs is how many pieces the two global inner products were summed in — which on a real machine is the number of workers. Iteration counts run from 271 to 277, 4 of them distinct, a spread of 2.2% of the work. Every run converged and every answer is right to the accuracy asked for; the forward errors span 7.12·10⁻¹¹ to 1.12·10⁻¹⁰, a factor of 1.58. What differs is not a digit at the end of an answer — it is the bill, and it is an integer.110¹267269271273275277279281pieces the inner products were summed initerations to the tolerance271, the cheapest run277, the dearestthe same solve, pricedpartitionings run13distinct counts4spread, per cent2.2best forward error7.1·10⁻¹¹worst1.1·10⁻¹⁰one matrix, one toleranceand the cost is the machine's

Conjugate gradients on a 200 × 200 symmetric positive definite matrix with κ = 1000, stopped when the relative residual falls below 10⁻¹⁰, run at each of 13 partition counts. The only thing that differs between the runs is how many pieces the two global inner products were summed in — which on a real machine is the number of workers. Iteration counts run from 271 to 277, 4 of them distinct, a spread of 2.2% of the work. Every run converged and every answer is right to the accuracy asked for; the forward errors span 7.12·10⁻¹¹ to 1.12·10⁻¹⁰, a factor of 1.58. What differs is not a digit at the end of an answer — it is the bill, and it is an integer.

logKappa: 5

The arguments are the ones A stopping test is a race passes. A value nobody placed would be a picture no essay asked for and no claim was ever checked against.

One system, one tolerance, and 9 different amounts of workConjugate gradients on a 200 × 200 symmetric positive definite matrix with κ = 10⁵, stopped when the relative residual falls below 10⁻¹⁰, run at each of 13 partition counts. The only thing that differs between the runs is how many pieces the two global inner products were summed in — which on a real machine is the number of workers. Iteration counts run from 1641 to 1655, 9 of them distinct, a spread of 0.9% of the work. Every run converged and every answer is right to the accuracy asked for; the forward errors span 7·10⁻¹¹ to 7.43·10⁻¹¹, a factor of 1.06. What differs is not a digit at the end of an answer — it is the bill, and it is an integer.110¹16371640164316461649165216551658pieces the inner products were summed initerations to the tolerance1641, the cheapest run1655, the dearestthe same solve, pricedpartitionings run13distinct counts9spread, per cent0.85best forward error7·10⁻¹¹worst7.4·10⁻¹¹one matrix, one toleranceand the cost is the machine's

Conjugate gradients on a 200 × 200 symmetric positive definite matrix with κ = 10⁵, stopped when the relative residual falls below 10⁻¹⁰, run at each of 13 partition counts. The only thing that differs between the runs is how many pieces the two global inner products were summed in — which on a real machine is the number of workers. Iteration counts run from 1641 to 1655, 9 of them distinct, a spread of 0.9% of the work. Every run converged and every answer is right to the accuracy asked for; the forward errors span 7·10⁻¹¹ to 7.43·10⁻¹¹, a factor of 1.06. What differs is not a digit at the end of an answer — it is the bill, and it is an integer.

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.

5 distinct claims across 5 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 conjugate gradients can finish on

and every answer is correct to the accuracy that was asked for

every run reached the tolerance it was given

LU is for square matrices

matmul shapes agree

Against the rule

It draws a decomposition and prints its residual. It calls cgAcrossPartitions, and every figure above carries the badge — which residualcheck verifies by looking for it in the emitted SVG rather than by finding the call that builds one. A badge that is constructed and then left out of the body is the failure that check exists for.

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.

The whole library · All essays · What must fail