Invalid use of operator

Matlab does not like the < in my function. Why?

if profit >= 60 && <100 % if profit falls between $60 and $100

any ideas? thank you.

function [output] = display_profit(dollars)
if profit >= 60 && <100    % if profit is between $60 and $100
end

Invalid use of operator (it directs me to the < which it has an issue with)

[Nikoleta]

I'm trying to raise to the power of two but it doesn't let me use .^2 or ^2. It says invalid use of operator.

[Image Analyst]

@Nikoleta start your own question in a new thread, and include your line of code. It could be your variable is not a numerical variable. If you don't show us your line of code and tell us what variable type then only Walter will be able to help you because only he has the Crystal Ball Toolbox ;-)

Answer 1

[John D'Errico]

That you know what your made up syntax means is great. But MATLAB cannot read your mind (yet, the mind reading toolbox has not been released.) Yes, you know what you intend there. :)

You wrote

if profit >= 60 && <100     

And somehow you think that MATLAB should know you intend it to be shorthard for this:

if profit >= 60 && profit < 100

But given your shorthand try, why would it not be equivalent to this one instead?

if profit >= 60 && 60 < 100

Computers are literal things. Don't use shorthand.

if profit >= 60 && profit < 100

[CamboSlice]

I've made this mistake MANY times haha. @John D'Errico answered correctly, albeit slightly harsh.

Answer 2

[Nikoleta]

I'm trying to run a code for pythagorean triplets. But when i raise a,b,c to the power of 2 it doesn't let me use ^2 or.^2 . My code looks something like this. I want to find all triplets that when i sum them i get 1000.

v=[a b c]
for a.^2 + b.^2 =c.^2 ;
    a < b < c ;
    if a + b + c==1000
        disp (v)
end

[Image Analyst]

I'm not sure why you posted here when I asked you to start your own discussion. Anyway, there are so many things wrong with this that it's clear you haven't even take the basic on-ramp training.

I'm not sure why you want to square anything if you "want to find all triplets that when i sum them i get 1000". Why don't you just use 3 nested for loops?

counter = 0;
for a = 1 : 999
    for b = 1 : 999
        for c = 1 : 999
            if (a + b + c) == 1000
                counter = counter + 1;
                fprintf('Combination #%d: %d + %d + %d = 1000\n', counter, a, b, c);
            end
        end
    end
end

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[Nikoleta]

Thank you. I'm just doing matlab for the first time so i don't really know what i'm doing, i'm just trying my best.But i might try that training, thank you for your help.