vecmat

std.linalg.vecmat · Level L0

Row vector times matrix.

(xᵀ·A)ⱼ = Σᵢ xᵢ·Aᵢⱼ

Signature

vecmat(x: f64[m], A: f64[m, n]) → f64[n]

Structure

The function as NOVA stores it: one box per input, operation and output, and arrows that carry values. A double border marks a call to another library function; select it to open that function.

xf64[m]Af64[m, n]ReshapexrMatMulyrReshapeyyf64[n]
  • input
  • operation
  • constant
  • call
  • output

Verification

  • Signature proven by NOVA’s shape solver, for every size.
  • Equal to the reference x @ A in exact rational arithmetic, on all 40 test cases.
  • All 136 float64 results inside the running error bound; the closest uses 75% of it.
  • Interpreter and NumPy backend return bit-identical results.
Accuracy in detail
correctly rounded (the float64 nearest the exact value)
79%
bit-equal to the NumPy formula in float64
100%
largest error, in units in the last place
11

Large ulp counts appear only where cancellation drives a result toward zero; the absolute error is still inside the bound.

Identity

Calls
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Called by
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sha256:019ef059173c7e93c3e0f9fa3928571535cd733b7028ece30083ef7d241d1c50

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