Set nan values

Why i can´t do this?

x550(:,2)(x550(:,2)<200)=nan

??? Error: ()-indexing must appear last in an index expression.

Best Regards

Answer 1

[Walter Roberson]

Because MATLAB does not allow () subscripting to be chained.

x550(x550(:,2)<200,2) = nan;

[Rafael Freire]

Thank you again Mr. Roberson.

Answer 2

[John D'Errico]

Because it is invalid MATLAB syntax. Wanting to do something does not make it possible.