Research Article

Photoplethysmography Biometric Recognition Model Based on Sparse Softmax Vector and k-Nearest Neighbor

Algorithm 1

Extracting sparse softmax vector of a testing sample.
Input: K-class subjects, training sample X and a testing sample y normalized with L2-norm, parameters , , , identity matrix I
Output: softmax vector of K-class
(1) initialize
(2) repeat
(3)  update
(4)  update
(5)  update
(6) until convergence
(7) let
(8) for each k in {1, 2, 3, … , K} do
(9)  let
(10)  let
(11) end for
(12) let
(13) output