Why is max(abs(S)) not working? S is a 1x40000 vector

S is a 1x40000 vector with negative values hence why im using the abs function but the error message keeps coming up. I have also tried max((abs(S(1,:))) but it has the same error message

"Array indices must be positive integers or logical values.

Error in Max (line 5)

max((abs(S)))"

load 'testhigh (1).dat'
S = (testhigh__1_(1, :)*10^3)*(1/49.500);
max((abs(S)))

Answer 1

[Walter Roberson]

Either max or abs is a variable at that point in the code.

[James Tursa]

@Saoirse I.e., you have inadvertently created variables in your workspace with these names that are shadowing the MATLAB functions. Don't use those names for variables.

[Walter Roberson]

In my observation, the two functions most commonly accidentally re-used as variable names are sum and max

[Stephen23]

Solution: rename those variables where they are created/referred to, clear the workspace, run your code again.