diff --git a/wk/Test_Non_Lin.m b/wk/Test_Non_Lin.m
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+%% Run linear simulation on a kr,kz grid and compute the non linear term afterwards
+clear all; close all;
+BASIC.SIMID = 'test_non_lin'; % Name of the simulations
+addpath(genpath('../matlab')) % ... add
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% outputs options
+OUTPUTS.nsave_0d = 0;
+OUTPUTS.nsave_1d = 0;
+OUTPUTS.nsave_2d = 1;
+OUTPUTS.nsave_5d = 1;
+OUTPUTS.write_Ni00 = '.true.';
+OUTPUTS.write_moments = '.true.';
+OUTPUTS.write_phi = '.true.';
+OUTPUTS.write_doubleprecision = '.true.';
+OUTPUTS.resfile0 = '''results''';
+%% Grid parameters
+GRID.pmaxe = 2;
+GRID.jmaxe = 2;
+GRID.pmaxi = 2;
+GRID.jmaxi = 2;
+GRID.nkr = 10;
+GRID.krmin = 0.0;
+GRID.krmax = 0.;
+GRID.nkz = 10;
+GRID.kzmin = 0.1;
+GRID.kzmax = 1.0;
+%% Model parameters
+MODEL.CO = -2; % Collision operator (0 : L.Bernstein, -1 : Full Coulomb, -2 : Dougherty)
+MODEL.nu = 0.01; % collisionality nu*L_perp/Cs0
+% temperature ratio T_a/T_e
+MODEL.tau_e = 1.0;
+MODEL.tau_i = 1.0;
+% mass ratio sqrt(m_a/m_i)
+MODEL.sigma_e = 0.0233380;
+MODEL.sigma_i = 1.0;
+% charge q_a/e
+MODEL.q_e =-1.0;
+MODEL.q_i = 1.0;
+% gradients L_perp/L_x
+MODEL.eta_n = 1.0; % Density
+MODEL.eta_T = 0.0; % Temperature
+MODEL.eta_B = 0.5; % Magnetic
+% Debye length
+MODEL.lambdaD = 0.0;
+%% Time integration and intialization parameters
+TIME_INTEGRATION.numerical_scheme = '''RK4''';
+BASIC.nrun = 100000;
+BASIC.dt = 0.05;
+BASIC.tmax = 1.0;
+INITIAL.initback_moments = 0.01;
+INITIAL.initnoise_moments = 0.;
+INITIAL.iseed = 42;
+INITIAL.selfmat_file = ...
+ ['''../iCa/self_Coll_GKE_0_GKI_0_ESELF_1_ISELF_1_Pmaxe_',num2str(GRID.pmaxe),...
+ '_Jmaxe_',num2str(GRID.jmaxe),'_Pmaxi_',num2str(GRID.pmaxi),'_Jmaxi_',...
+ num2str(GRID.jmaxi),'_pamaxx_10.h5'''];
+INITIAL.eimat_file = ...
+ ['''../iCa/ei_Coll_GKE_0_GKI_0_ETEST_1_EBACK_1_Pmaxe_',num2str(GRID.pmaxe),...
+ '_Jmaxe_',num2str(GRID.jmaxe),'_Pmaxi_',num2str(GRID.pmaxi),'_Jmaxi_',...
+ num2str(GRID.jmaxi),'_pamaxx_10_tau_1.0000_mu_0.0233.h5'''];
+INITIAL.iemat_file = ...
+ ['''../iCa/ie_Coll_GKE_0_GKI_0_ITEST_1_IBACK_1_Pmaxe_',num2str(GRID.pmaxe),...
+ '_Jmaxe_',num2str(GRID.jmaxe),'_Pmaxi_',num2str(GRID.pmaxi),'_Jmaxi_',...
+ num2str(GRID.jmaxi),'_pamaxx_10_tau_1.0000_mu_0.0233.h5'''];
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% Write input file and run HeLaZ
+INPUT = write_fort90(OUTPUTS,GRID,MODEL,INITIAL,TIME_INTEGRATION,BASIC);
+nproc = 1;
+EXEC = ' ../bin/helaz ';
+RUN = ['mpirun -np ' num2str(nproc)];
+CMD = [RUN, EXEC, INPUT];
+system(CMD);
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% Run MOLI for each grid point and save the moments evolution
+kr_scan = linspace(GRID.krmin,GRID.krmax,GRID.nkr);
+kz_scan = linspace(GRID.kzmin,GRID.kzmax,GRID.nkz);
+Nmtot = (GRID.pmaxe+1) * (GRID.jmaxe+1) + (GRID.pmaxi+1) * (GRID.jmaxi+1);
+Nt = floor(BASIC.tmax/BASIC.dt)+1;
+Napj_2D = zeros(GRID.nkr,GRID.nkz,Nt,Nmtot);
+params.RK4 = 1;
+for ikr = 1:GRID.nkr
+ for ikz = 1:GRID.nkz
+ kr = kr_scan(ikr); % used by MOLI_time_solver_2D directly
+ kz = kz_scan(ikz);
+ run ../matlab/MOLI_time_solver_2D
+ Napj_2D(ikr,ikz,:,:) = results.Napj;
+ end
+end
+%% Compute non linear term
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% Analysis and basic figures
+default_plots_options
+SAVEFIG = 1;
+filename = 'results_00.h5';
+default_plots_options
+TITLE = [TITLE,', $k_z=',num2str(GRID.kzmin),'$'];
+if params.RK4; MOLIsolvername = 'RK4';
+else; MOLIsolvername = 'ode15i';
+end
+bare = @(p_,j_) (GRID.jmaxe+1)*p_ + j_ + 1;
+bari = @(p_,j_) bare(GRID.pmaxe, GRID.jmaxe) + (GRID.jmaxi+1)*p_ + j_ + 1;
+
+%% Convert MOLI moments into HeLaZ format
+Nepj_MOLI = zeros(GRID.pmaxe+1, GRID.jmaxe+1,GRID.nkr,GRID.nkz,Nt);
+for ip = 1:GRID.pmaxe+1
+ for ij = 1:GRID.jmaxe+1
+ Nepj_MOLI(ip,ij,:,:,:) = Napj_2D(:,:,:,bare(ip-1,ij-1));
+ end
+end
+Nipj_MOLI = zeros(GRID.pmaxi+1, GRID.jmaxi+1,GRID.nkr,GRID.nkz,Nt);
+for ip = 1:GRID.pmaxi+1
+ for ij = 1:GRID.jmaxi+1
+ Nipj_MOLI(ip,ij,:,:,:) = Napj_2D(:,:,:,bari(ip-1,ij-1));
+ end
+end
+%% Load HeLaZ moments
+
+moment = 'moments_i';
+
+kr = h5read(filename,['/data/var5d/' moment '/coordkr']);
+kz = h5read(filename,['/data/var5d/' moment '/coordkz']);
+time = h5read(filename,'/data/var5d/time');
+Nipj_HeLaZ = zeros(GRID.pmaxi+1, GRID.jmaxi+1,numel(kr),numel(kz),numel(time));
+for it = 1:numel(time)
+ tmp = h5read(filename,['/data/var5d/', moment,'/', num2str(it,'%06d')]);
+ Nipj_HeLaZ(:,:,:,:,it) = tmp.real + 1i * tmp.imaginary;
+end
+
+moment = 'moments_e';
+
+kr = h5read(filename,['/data/var5d/' moment '/coordkr']);
+kz = h5read(filename,['/data/var5d/' moment '/coordkz']);
+time = h5read(filename,'/data/var5d/time');
+Nepj_HeLaZ = zeros(GRID.pmaxe+1, GRID.jmaxe+1,numel(kr),numel(kz),numel(time));
+for it = 1:numel(time)
+ tmp = h5read(filename,['/data/var5d/', moment,'/', num2str(it,'%06d')]);
+ Nepj_HeLaZ(:,:,:,:,it) = tmp.real + 1i * tmp.imaginary;
+end
+
+%% Check coherence of linear results
+disp('MOLI - HeLaZ differences :');
+disp(sum(sum(sum(sum(sum(Nipj_MOLI-Nipj_HeLaZ)))))...
+ / sum(sum(sum(sum(sum(Nipj_MOLI))))));
+
+%% Non linear term computation
+%get phi
+phiHeLaZ = zeros(numel(timephi),numel(kr),numel(kz));
+for it = 1:numel(time)
+ tmp = h5read(filename,['/data/var2d/phi/' num2str(it,'%06d')]);
+ phiHeLaZ(it,:,:) = tmp.real + 1i * tmp.imaginary;
+end
+
+compute_Sapj
+