domain error. to compute complex results from real x, use 'log(complex(x))'

hello, I'm having trouble with the domain error. to compute complex results from real x, use 'log(complex(x))' on my project fuel cell. how to handle it?

Answer 1

[Walter Roberson]

At some point your x becomes negative. MATLAB proper would handle the situation by creating a complex result, but Simulink generates an error message because such situations in Simulink often result from an incorrect model or omission in thinking about the model

[farid]

is it possible to ignore it to generate ?

[Walter Roberson]

When your x goes negative what results would you want from the log()? If you want the log of the absolute value of x then code the log of the absolute value of x.