Add matfaust.lazylinop.sum with its doc.

[skip ci]

gen_doc/CMakeLists.txt

@@ -31,7 +31,7 @@ if(BUILD_DOCUMENTATION)
 			string(CONCAT DOXYGEN_FILE_PATTERNS "*.cpp *.hpp *.h *.cu *.hu")
 		endif()
 		if(BUILD_WRAPPER_MATLAB)
-			string(CONCAT DOXYGEN_FILE_PATTERNS ${DOXYGEN_FILE_PATTERNS} " Faust.m FaustMulMode.m StoppingCriterion.m ConstraintGeneric.m ConstraintMat.m ConstraintReal.m ConstraintInt.m ConstraintName.m ParamsFact.m ParamsHierarchical.m ParamsPalm4MSA.m FaustFactory.m hadamard.m quickstart.m fft.m bsl.m runtimecmp.m runall.m version.m faust_fact.m ParamsHierarchicalSquareMat.m ParamsHierarchicalRectMat.m license.m omp.m wht.m dft.m eye.m rand.m rand_bsr.m eigtj.m hierarchical.m fact.m palm4msa.m fgft_givens.m fgft_palm.m svdtj.m splin.m spcol.m proj_gen.m sp.m const.m supp.m hankel.m toeplitz.m circ.m normcol.m normlin.m splincol.m blockdiag.m skperm.m enable_gpu_mod.m is_gpu_mod_enabled.m isFaust.m poly.m basis.m next.m expm_multiply.m FaustPoly.m MHTPParams.m palm4msa_mhtp.m hierarchical_mhtp.m butterfly.m ParamsHierarchicalDFT.m create_bsr.m ParamsPalm4msaWHT.m proj_id.m ParamsHierarchicalNoResCons.m ParamsHierarchicalWHTNoResCons.m ParamsHierarchicalRectMatNoResCons.m circ.m anticirc.m toeplitz.m dct.m dst.m rand_butterfly.m opt_butterfly_faust.m bitrev_perm.m LazyLinearOp.m asLazyLinearOp.m isLazyLinearOp.m LazyLinearOpKron.m kron.m aslazylinearoperator.m LazyLinearOperator.m diag.m blkdiag.m ") # warning: the space on the end matters
+			string(CONCAT DOXYGEN_FILE_PATTERNS ${DOXYGEN_FILE_PATTERNS} " Faust.m FaustMulMode.m StoppingCriterion.m ConstraintGeneric.m ConstraintMat.m ConstraintReal.m ConstraintInt.m ConstraintName.m ParamsFact.m ParamsHierarchical.m ParamsPalm4MSA.m FaustFactory.m hadamard.m quickstart.m fft.m bsl.m runtimecmp.m runall.m version.m faust_fact.m ParamsHierarchicalSquareMat.m ParamsHierarchicalRectMat.m license.m omp.m wht.m dft.m eye.m rand.m rand_bsr.m eigtj.m hierarchical.m fact.m palm4msa.m fgft_givens.m fgft_palm.m svdtj.m splin.m spcol.m proj_gen.m sp.m const.m supp.m hankel.m toeplitz.m circ.m normcol.m normlin.m splincol.m blockdiag.m skperm.m enable_gpu_mod.m is_gpu_mod_enabled.m isFaust.m poly.m basis.m next.m expm_multiply.m FaustPoly.m MHTPParams.m palm4msa_mhtp.m hierarchical_mhtp.m butterfly.m ParamsHierarchicalDFT.m create_bsr.m ParamsPalm4msaWHT.m proj_id.m ParamsHierarchicalNoResCons.m ParamsHierarchicalWHTNoResCons.m ParamsHierarchicalRectMatNoResCons.m circ.m anticirc.m toeplitz.m dct.m dst.m rand_butterfly.m opt_butterfly_faust.m bitrev_perm.m LazyLinearOp.m asLazyLinearOp.m isLazyLinearOp.m LazyLinearOpKron.m kron.m aslazylinearoperator.m LazyLinearOperator.m diag.m blkdiag.m sum.m ") # warning: the space on the end matters
 		endif()
 		if(BUILD_WRAPPER_PYTHON)
 			string(CONCAT DOXYGEN_FILE_PATTERNS ${DOXYGEN_FILE_PATTERNS} "__init__.py factparams.py demo.py tools.py fact.py proj.py poly.py lazylinop.py")

wrapper/matlab/+matfaust/+lazylinop/sum.m

+%=============================================================
+%> @brief Sums (lazily) all linear operators in varargin.
+%>
+%> @param varargin: the operators to add up.
+%>
+%> @retval LS the LazyLinearOp for the sum.
+%>
+%> @b Example:
+%> @code
+%> >> import matfaust.dft
+%> >> d = 32;
+%> >> H = dft(32);
+%> >> v = rand(d, 1);
+%> >> D = spdiags(v, 0, d, d);
+%> >> HDH = H * matfaust.Faust(D) * H;
+%> >> terms = {}; for i=1:10; terms = [ terms {HDH} ];end
+%> >> LS = matfaust.lazylinop.sum(terms{:});
+%>
+%> ans =
+%>
+%>     32    32
+%>
+%> >> M = rand(size(LS, 2), 13);
+%> >> LS * M
+%> @endcode
+%=============================================================
+function LS = sum(varargin)
+	import matfaust.lazylinop.LazyLinearOperator
+	% TODO: check varargin is composed of numerical arrays or compatible operators
+	lAx = @(A, x) A * x;
+	lAHx = @(A, x) A' * x;
+	n = length(varargin);
+	function P = matmat(x, lmul)
+		P = lmul(varargin{1}, x);
+		for i=2:n
+			A = varargin{i};
+			P = P + lmul(A, x);
+		end
+	end
+	LS = LazyLinearOperator(size(varargin{1}), 'matmat', @(x) matmat(x, lAx), 'rmatmat', @(x) matmat(x, lAHx));
+end