Problem with undefined function

Here , it a part of my code.

PGA=[1.0000000e-01,2.0000000e-01,4.0000000e-01,9.00000e-01,1.00000e+00,1.4000000e+00,0.500000e+00,1.700000e+00,2.00000e+00,2.5000000e+00,2.800000e+00,3.5000000e+00].';

Z1=log(PGA/th1)/b1;

for i=0:1:11

if Z1(i+1)<0

Z1(i+1)=Z1(i+1)+1;

P1=logncdf(Z1(i+1));

else

P1=logncdf(Z1(i+1));

end

P1(i+1)=P1;

end

disp(P1);

Error message:

Undefined function 'logncdf' for input arguments of type 'double'.

Error in excersise_1 (line 25)

P1=logncdf(Z1(i+1));

Answer 1

[Paul]

logncdf is a function in the Statistics and Machine Learning Toolbox. That toolbox needs to be installed and it will have to be included on your license.

Answer 2

[Torsten]

An alternative without the toolbox:

logncdf_user = @(x,mu,sigma) 0.5*(erf((log(x)-mu)/(sqrt(2)*sigma))+1);
x=0:0.1:10;
hold on
plot(x,logncdf_user(x,0,1))
plot(x,logncdf(x,0,1))
hold off
grid on