Sparse Recovery by Semi-Iterative Hard Thresholding Algorithm

<table> Recover error versus sparsity with fixed <svg height="12.4375" id="M140" style="vertical-align:-0.1638pt" version="1.1" viewbox="0 0 165.14999 12.4375" width="165.14999" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg>: (a) Gaussian sparse vectors and (b) sparse <svg height="11.2875" id="M141" style="vertical-align:-0.3003pt" version="1.1" viewbox="0 0 18.262501 11.2875" width="18.262501" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg> spikes  vectors. </table>

Mathematical Problems in Engineering

Sparse Recovery by Semi-Iterative Hard Thresholding Algorithm

Figure 3