exponential_quantile
std.stats.exponential_quantile · Level L5The exponential distribution's quantile: −log(1 − p)/λ, written with log1p so that small p keep their relative accuracy.
F⁻¹(p) = −log(1 − p)/λ
Signature
exponential_quantile(p: f64[n], rate: f64[]) → 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 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.
- Agrees with the reference
−np.log(1 − p)/rateto 80 digits (100-digit arithmetic), on all 40 test cases. - All 165 float64 results inside the running error bound; the closest uses 20% of it.
- Interpreter and NumPy backend return bit-identical results.
- At float32 too: the 40 test cases rounded to float32, and 40 of them inside the running error bound at u = 2⁻²⁴; the closest uses 19% of it.
Accuracy in detail
- correctly rounded (the float64 nearest the exact value)
- 75%
- bit-equal to the NumPy formula in float64
- 66%
- largest error, in units in the last place
- 1.75
Identity
Calls
—
Called by
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sha256:42fcf774f8711388e51a35b94f26dafc66e0f194fe4696fc1d1c35c596fe3362The semantic hash of the graph. It changes when the program changes, and never when only its documentation does.
Control handle
- Symbol
- Ω:std.stats.exponential_quantile · Ω:exponential_quantile
- Pins
sha256:1881d9614af7b40c8572ff9d2594773688a3991efe211b9fae01e3f2abe38a03this graph alone- Evidence
sha256:5de17c1fb95b8a810d9f365c4021182ea28afb004c73aa829dbd48f19dfebf9ethe 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.