tm_run

std.seq.tm_run · Level L3

Run a deterministic Turing machine for s steps (s the length of steps, only its length read) from the start state with the head on cell 0 of the listed tape: a Scan of tm_step. Returns the final state, head and tape, whether the head ever tried to leave the listed tape, and whether the machine has halted. A finite trace settles that one input only: a run that has not halted proves neither rejection nor non-termination, and one halting trace does not make the machine a decider.

(q, h, τ) after s steps of tm_step

Signature

tm_run(start: f64[], tape: f64[T], steps: f64[s], Next: i64[g, c], Write: i64[g, c], Move: i64[g, c], halting: f64[g]) → f64[], f64[], f64[T], f64[], f64[]

Structure

The function as NOVA stores it: one box per input, operation and output, and arrows that carry values. A double border marks another library function this one runs — called once, or by Scan once per element; select it to open that function.

input
operation
constant
call
output

Verification

Signature proven by NOVA’s shape solver, for every size.
Equal to the reference the same steps on Python lists in exact rational arithmetic, on all 40 test cases.
All 320 float64 results are exact: the error is zero.
Interpreter and NumPy backend return bit-identical results.
At float32 too: the 40 test cases rounded to float32, and 40 of them exact, with zero error.

Accuracy in detail

correctly rounded (the float64 nearest the exact value): 100%
bit-equal to the NumPy formula in float64: 100%
largest error, in units in the last place: 0

Identity

Calls

tm_step

Called by

—

sha256:3f282e2de3da16b50796fd571d3b4368d784f849b64a66317bb14ce9316530c4

The semantic hash of the graph. It changes when the program changes, and never when only its documentation does.

Control handle

Symbol: Ω:std.seq.tm_run · Ω:tm_run
Pins: sha256:5a4172161f6cf4ed2b30c64c2fdf0eb7d74664159e20b696626cd0d3be5e1314this graph and the 1 it reaches through calls
Evidence: sha256:8e6d98619f53acaabb5f0d70b01657e03162ed96f0a3b87c4b8249e9463d527dthe hash of its verification record
Needs: no capability: a pure function

Through NOVA’s control layer, the symbol launches this function only while the program still matches what it pins: a change to this graph, or to any graph it reaches, needs a migration first.