The Multiple-Lanczos Bi-Conjugate Gradient stabilized (ML(k)-BiCGStab) solver is an 'improvement' of the standard BiCgStab solver.
The algorithm was taken from: ML(k)BiCGSTAB: A BiCGSTAB variant based on multiple Lanczos starting vectors Man-chung Yeung and Tony F. Chan SIAM Journal of Scientific Computing Volume 21, Number 4, pp. 1263 - 1290
The example code below provides an indication of the possible use of the solver.
Must be larger than 1 and smaller than the number of variables in the matrix that for which this solver will be used.