Why, Array indices must be positive integers or logical values

P=450000 r=0.042 M=P(r/12) Error array indices must be positive or logical values.

Can someone please help me Why is it saying this

Answer 1

[Star Strider]

It is saying that because ‘r’ is not an integer, and even if it was, there are only some instances in which ‘r/12’ would be an integer greater than 0.

Aside from that, ‘P’ is a scalar, so any subscript vallue other than 1 would not be valid.

However I suspect you are missing an multiplication operator, so that the assignment should be:

M = P.*(r/12)

since MATLAB does not recognise implicit multiplication.