Too many Output Arguments

Hi, I don't know why this code is giving me this error.

Initially the output argument E was not used. But I realized I need this value for some stuff I want to do afterwards. Why is it now giving me this error. I never got it before when I used this code with only the three output arguments. Please help!

function [nbar,sig,ChiSqrd,E]=VerifyP_Stats(X)
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% This function takes in counts from a counting experiment, X, 
% and performs experimental statistics, as outlined in the
% lab manaual for Radio Active Decay 
% (http://physwiki.apps01.yorku.ca/index.php?title=Main_Page/PHYS_3220/Radi
% oactive_Decays).
% It returns the experimental mean (nbar), experimental standard deviation
% (sig), and the chi squared value using the formula for a Poisson
% distribution as outline in the above manual.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
N=numel(X);
O=ErrorCalc_ObservedK(X);
n=size(O,1);
Pn=linspace(0,0,n);
nPn=linspace(0,0,n);
SigN=linspace(0,0,n);
En=linspace(0,0,n);
preChi=linspace(0,0,n);
for i=1:n
    Pn(i)=O(i,2)/N;
    nPn(i)=O(i,1)*Pn(i);
end
nbar=sum(nPn);
for i=1:n
    SigN(i)=((O(i,1)-nbar)^2)*Pn(i);
    En(i)=(N*exp(-nbar)*(nbar)^O(i,1))/factorial(O(i,1));
    preChi(i)=((O(i,2)-En(i))^2)/En(i);
end
ChiSqrd=sum(preChi);
sig=sqrt(sum(SigN));
E=En;
end

[samjhana rai]

hello,

im trying to perform to find the optimla placement of the FACTS devices but im getting error as "too many output arguments" i m not sure what the prblem is.

function [fxmin, xmin] = ORPD_30bus()

clc

clear all

warning off all

global Ybus Yf Yt;

%% define named indices into bus, gen, branch matrices

[PQ, PV, REF, NONE, BUS_I, BUS_TYPE, PD, QD, GS, BS, BUS_AREA, VM, ...

VA, BASE_KV, ZONE, VMAX, VMIN, LAM_P, LAM_Q, MU_VMAX, MU_VMIN] = idx_bus;

[F_BUS, T_BUS, BR_R, BR_X, BR_B, RATE_A, RATE_B, RATE_C, ...

TAP, SHIFT, BR_STATUS, PF, QF, PT, QT, MU_SF, MU_ST, ...

ANGMIN, ANGMAX, MU_ANGMIN, MU_ANGMAX] = idx_brch;

[GEN_BUS, PG, QG, QMAX, QMIN, VG, MBASE, GEN_STATUS, PMAX, PMIN, ...

MU_PMAX, MU_PMIN, MU_QMAX, MU_QMIN, PC1, PC2, QC1MIN, QC1MAX, ...

QC2MIN, QC2MAX, RAMP_AGC, RAMP_10, RAMP_30, RAMP_Q, APF] = idx_gen;

[baseMVA, bus, gen, branch, areas, gencost]=case_ieee30; %Input data of IEEE 30 bus test system

% Determine the value of weight change

w_start = 1; %Initial inertia weight's value

w_end = 0.20; %Final inertia weight

w_varyfor = floor(0.7*100);

w_now = w_start;

inertdec = (w_start-w_end)/w_varyfor; %Inertia weight's change per iteration

iter=0;

% Initialize size of Swarm, no. of control varialbes and Velocity

%size of swarm=50 (user may change it), no. of control variables=vg1, vg2,

%vg5,vg8, vg11, vg13 (Generator bus voltage in pu), T1, T2, T3, T4

%(Transformer tap position), QC3, QC10, QC24 (Injected reactive power of

%capacitors in MVAR)

Swarm=[unifrnd(0.90,1.10,50,6),unifrnd(0.95,1.05,50,4),unifrnd(1,20,50,3)];

VStep =[unifrnd(0.04,0.04,50,6),unifrnd(0.002,0.002,50,4), unifrnd(4,4,50,3)];

for i=1:50 % no of particles

global bus gen branch v1 v2 v5 v8 v11 v13

v1=Swarm(i,1);

v2=Swarm(i,2);

v5=Swarm(i,3);

v8=Swarm(i,4);

v11=Swarm(i,5);

v13=Swarm(i,6);

bus(1,VM)=Swarm(i,1);

bus(2,VM)=Swarm(i,2);

bus(5,VM)=Swarm(i,3);

bus(8,VM)=Swarm(i,4);

bus(11,VM)=Swarm(i,5);

bus(13,VM)=Swarm(i,6);

gen(1,VG)=Swarm(i,1); % gen1

gen(2,VG)=Swarm(i,2); %gen2

gen(3,VG)=Swarm(i,3); %gen5

gen(4,VG)=Swarm(i,4); %gen8

gen(5,VG)=Swarm(i,5); %gen11

gen(6,VG)=Swarm(i,6); %gen13

branch(11,TAP)=Swarm(i,7);% T1, transformer tap

branch(12,TAP)=Swarm(i,8); %T2

branch(15,TAP)=Swarm(i,9); %T3

branch(36,TAP)=Swarm(i,10); %T4

bus(3,BS)=Swarm(i,11); % QC3, capacitor

bus(10,BS)=Swarm(i,12); % QC10, capacitor

bus(24,BS)=Swarm(i,13); % QC24, capacitor

global bus gen branch Yf Yt Ybus

[Ybus, Yf, Yt] = makeYbus(baseMVA, bus, branch);% construct Ybus

[MVAbase,bus,gen,branch,success,et]=runpf; % run NR load flow

global V

global Ybus

bbb=branch(:,[PF,QF]).^2; % ans. is P(from)^2, Q(from)^2

ccc=bbb';

ddd=(sum(ccc))';

eee=sqrt(ddd); %actual values of apparent powers "From bus injection"

fff=branch(:,[PT,QT]).^2;

ggg=fff';

hhh=(sum(ggg))';

iii=sqrt(hhh); %actual values of apparent powers "To bus injection"

jjj=[];

for count_1=1:41 % jjj will contain actual max. apparent power.("from" bus power is compared with "to" bus power)

if eee(count_1)>=iii(count_1)

jjj(count_1)=eee(count_1);

else

jjj(count_1)=iii(count_1);

end

end

%penalty value calculation for line flow violations

for count_2=1:41 % max power is compared with thermal limit

if jjj(count_2)>branch(count_2, RATE_A)

kkk(count_2)=10000*((jjj(count_2)-branch((count_2), RATE_A))^2); % if limit violates,penalty is imposed

else

kkk(count_2)=0; %if no violation, penalty is zero

end

end

penalty_line=sum(kkk);% summation of all penalty of line flow violations

%penalty value calculation for bus voltage violation

lll=bus(:,VM); % voltage mag. of each bus

for count_3=1:30

if lll(count_3)>bus(count_3,VMAX)

penalty_volt(count_3)=10000*(lll(count_3)-bus(count_3,VMAX))^2;

elseif lll(count_3)<bus(count_3,VMIN)

penalty_volt(count_3)=10000*(bus(count_3,VMIN)-lll(count_3))^2;

else

penalty_volt(count_3)=0;

end

end

penalty_volt=sum(penalty_volt);%summation of penalty for bus voltage violation

%penalty value calculation for reactive power violation of all

%generators(PV buses and slack bus)

mmm=gen(:,QG);% reactive power output of all generators

for count_4=1:6

if mmm(count_4)>gen(count_4,QMAX)

penalty_reactive(count_4)=10000*((mmm(count_4)-gen(count_4,QMAX))^2);

elseif mmm(count_4)<gen(count_4,QMIN)

penalty_reactive(count_4)=10000*((gen(count_4,QMIN)-mmm(count_4))^2);

else

penalty_reactive(count_4)=0;

end

end

penalty_reactive=sum(penalty_reactive);%summation of penalty for Q limit violation

%penalty value calculation for P violation of slack generator

nnn=gen(:,PG);

if nnn(1,1)>gen(1,PMAX)

penalty_slack=1000*((nnn(1,1)-gen(1,PMAX))^2);

elseif nnn(1,1)<gen(1,PMIN)

penalty_slack=1000*((gen(1,PMIN)-nnn(1,1))^2);

else

penalty_slack=0;

end

%sum of all penalties, penalty function is used to handle inequality

%constraints

global penalty_function

penalty_function=(penalty_slack)+ (penalty_reactive)+(penalty_volt)+(penalty_line);

%sum of real power losses of all branches

global loss

sum_P_loss=(sum(real(loss)));

global penalty_function

fun_Swarm=(sum_P_loss)+(penalty_function);

% Objective function= sum of active power losses of the transmission lines

fSwarm(i,:)=sum_P_loss;

end

% Initializing the Best positions matrix and

% the corresponding function values

PBest = Swarm;

fPBest = fSwarm;

% Finding best particle in initial population

[fGBest, g] = min(fSwarm);

lastbpf = fGBest;

Best = Swarm(g,:); %Used to keep track of the Best particle ever

fBest = fGBest;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%% THE PSO LOOP %%

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

while( iter < 200 )% no of iterations

global iter

iter = iter+1;

if iter>190

diary on

end

% Update the value of the inertia weight w

if (iter<=w_varyfor) & (iter > 1)

w_now = w_now - inertdec; %Change inertia weight

end

% The PLAIN PSO %

% Set GBest

A = repmat(Swarm(g,:), 50, 1); %A = GBest. repmat(X, m, n) repeats the matrix X in m rows by n columns, 50=no. of particles

% Generate Random Numbers

R1 = rand(50, 13); % 50=No. of particles, 13=dimension of the problem(size of swarm=no. of variables)

R2 = rand(50, 13);

% Calculate Velocity

VStep = w_now*VStep + 2.1*R1.*(PBest-Swarm) + 2.0*R2.*(A-Swarm);% c1=2.1, c2=2

% Apply Vmax Operator for v > Vmax

changeRows = VStep > 0.003;

VStep(find(changeRows)) = 0.003;

% Apply Vmax Operator for v < -Vmax

changeRows = VStep < -0.003;

VStep(find(changeRows)) = -0.003;

% ::UPDATE POSITIONS OF PARTICLES::

Swarm = Swarm + 0.729 * VStep; % Evaluate new Swarm, Chi=0.729

for j=1:50 %no of particles

v1=Swarm(j,1);

v2=Swarm(j,2);

v5=Swarm(j,3);

v8=Swarm(j,4);

v11=Swarm(j,5);

v13=Swarm(j,6);

bus(1,VM)=Swarm(j,1);

bus(2,VM)=Swarm(j,2);

bus(5,VM)=Swarm(j,3);

bus(8,VM)=Swarm(j,4);

bus(11,VM)=Swarm(j,5);

bus(13,VM)=Swarm(j,6);

gen(1,VG)=Swarm(j,1); % gen1

gen(2,VG)=Swarm(j,2); %gen2

gen(3,VG)=Swarm(j,3); %gen5

gen(4,VG)=Swarm(j,4); %gen8

gen(5,VG)=Swarm(j,5); %gen11

gen(6,VG)=Swarm(j,6); %gen13

branch(11,TAP)=Swarm(j,7);% T1, transformer tap

branch(12,TAP)=Swarm(j,8); %T2

branch(15,TAP)=Swarm(j,9); %T3

branch(36,TAP)=Swarm(j,10); %T4

bus(3,BS)=Swarm(j,11); % QC3, capacitor

bus(10,BS)=Swarm(j,12); % QC10, capacitor

bus(24,BS)=Swarm(j,13); % QC24, capacitor

[Ybus, Yf, Yt] = makeYbus(baseMVA, bus, branch);

[MVAbase,bus,gen,branch,success,et]=runpf;

global V

bbb=branch(:,[PF,QF]).^2; % ans. is P(from)^2, Q(from)^2

ccc=bbb';

ddd=(sum(ccc))';

eee=sqrt(ddd); %actual values of apparent powers "From bus injection"

fff=branch(:,[PT,QT]).^2;

ggg=fff';

hhh=(sum(ggg))';

iii=sqrt(hhh); %actual values of apparent powers "To bus injection"

jjj=[];

for count_1=1:41 % jjj will contain actual max. apparent power.("from" bus power is compared with "to" bus power)

if eee(count_1)>=iii(count_1)

jjj(count_1)=eee(count_1);

else

jjj(count_1)=iii(count_1);

end

end

%penalty value calculation for line flow violations

for count_2=1:41 % max power is compared with thermal limit

if jjj(count_2)>branch(count_2, RATE_A)

kkk(count_2)=10000*((jjj(count_2)-branch((count_2), RATE_A))^2); % if limit violates,penalty is imposed

else

kkk(count_2)=0; %if no violation, penalty is zero

end

end

penalty_line=sum(kkk);% summation of all penalty of line flow violations

%penalty value calculation for bus voltage violation

lll=bus(:,VM); % voltage mag. of each bus

for count_3=1:30

if lll(count_3)>bus(count_3,VMAX)

penalty_volt(count_3)=10000*(lll(count_3)-bus(count_3,VMAX))^2;

elseif lll(count_3)<bus(count_3,VMIN)

penalty_volt(count_3)=10000*(bus(count_3,VMIN)-lll(count_3))^2;

else

penalty_volt(count_3)=0;

end

end

penalty_volt=sum(penalty_volt);%summation of penalty for bus voltage violation

%penalty value calculation for reactive power violation of all

%generators(PV buses and slack bus)

mmm=gen(:,QG);% reactive power output of all generators

for count_4=1:6

if mmm(count_4)>gen(count_4,QMAX)

penalty_reactive(count_4)=10000*((mmm(count_4)-gen(count_4,QMAX))^2);

elseif mmm(count_4)<gen(count_4,QMIN)

penalty_reactive(count_4)=10000*((gen(count_4,QMIN)-mmm(count_4))^2);

else

penalty_reactive(count_4)=0;

end

end

penalty_reactive=sum(penalty_reactive);%summation of penalty for Q limit violation

%penalty value calculation for P violation of slack generator

nnn=gen(:,PG);

if nnn(1,1)>gen(1,PMAX)

penalty_slack=1000*((nnn(1,1)-gen(1,PMAX))^2);

elseif nnn(1,1)<gen(1,PMIN)

penalty_slack=1000*((gen(1,PMIN)-nnn(1,1))^2);

else

penalty_slack=0;

end

%sum of all penalties

global penalty_function

penalty_function=(penalty_slack)+ (penalty_reactive)+(penalty_volt)+(penalty_line);

%sum of real power losses of all branches

global loss

sum_P_loss=(sum(real(loss)))

global penalty_function

fun_Swarm=(sum_P_loss)+(penalty_function);

fSwarm(j,:)=sum_P_loss;

end

% Updating the best position for each particle

changeRows = fSwarm < fPBest; % latest fswarm-previous fswarm

fPBest(find(changeRows)) = fSwarm(find(changeRows)); %fitness value

PBest(find(changeRows), :) = Swarm(find(changeRows), :); %position

lastbpart = PBest(g, :);

% Updating index g

[fGBest, g] = min(fPBest);

%Update Best. Only if fitness has improved.

if fGBest < lastbpf

[fBest, b] = min(fPBest);

fbest(iter) = fBest;

figure(1);

plot(fbest, '-b' );

title('Total Active power losses (MW)');

xlabel('Iteration number');

ylabel('Total Active power losses (MW)');

fBest;

Best = PBest(b,:);

end

end

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%% END OF PSO LOOP %%

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

[fxmin, b] = min(fPBest)

xmin = PBest(b, :)

%diary off

return

please do comment if anyone of you know.

Answer 1

[Star Strider]

Usually, the ‘too many output arguments’ error occurs in your calling script, when you ask for more outputs than the function provides. My guess is that you either have a copy of your previous function (with three outputs) in another directory and your new script code is calling it instead, or that you have a variable in your script called ‘VerifyP_Stats’. The easiest way to solve the problem of two functions having the same name is to rename one of them (for example call this one ‘VerifyP_Stats4’ or something), and change your call to it.

An easy way to see if you are shadowing ‘VerifyP_Stats’ with another function or a variable is to enter this in the Command Window:

which VerifyP_Stats -all

The results will tell you.

I don’t have your code, so I’m purely guessing.

[Francesco De Chellis]

I did that, and only the one instance of it showed up.

The code I'm using to call this function that gives the error is:

[T_nbar T_sig T_CS T_E]=VerifyP_Stats(Z_lrg(:,2));

[Francesco De Chellis]

Actually, you were right. I found another copy of the same script, and that must be why it was giving me this error, as you suggested.

I wonder why the which command didn't notify me of the other script. Is it possibly because it wasn't in the same folder?

Either way, thanks for your help!!!

[Star Strider]

My pleasure!

I’m surprised which didn’t find both. It only looks on the MATLAB search path, so there is a possibility that the other directory isn’t on it. See the documentation for addpath (and its friends) for details on including all the directories you want MATLAB to know about.