cs_guarantee

Builtin index · Noise

result = cs_guarantee(A)

Input: A · Output: result

What it is

A is an M×N sensing matrix.

Overloads

One call shape — this function is not overloaded.

Code	Input	Output	Description
`result = cs_guarantee(A)`	`A` matrixnot documented yet	`result` number or matrix	Returns a single number: the largest sparsity level that the matrix's coherence alone can prove recoverable. Badly pessimistic, and the only certificate that is computable at all.

Examples

From the documentation, and run by the build -- the output and the figure below are what the engine actually produced. Simplest first.

A = randn(60, 200, seed = 7) / sqrt(60)
print("coherence {coherence(A):.3f}, provable sparsity {cs_guarantee(A)}")

output

coherence 0.558, provable sparsity 1

from compressed-sensing

How it works

cs_guarantee(A) — the largest sparsity coherence alone can PROVE recoverable. Badly pessimistic, and the only certificate that is computable at all; see the module doc.

From the note above this builtin in the interpreter, where the reasoning was written down as it was built.