# Error Using ^ When Typing Power Command

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Duong Nguyen on 17 Jan 2018
Commented: Duong Nguyen on 17 Jan 2018
I want to plot a graph of y versus t with:
>> t = linspace(0,10,20);
>> y = 1/(t*(3/10^(8*8)*10^(3/2))/2 + 1)^(2/3);
But when I finished writing the second line, the error appeared: Error using ^ One argument must be a square matrix and the other must be a scalar. Use POWER (.^) for elementwise power. So how can I solve this problem?
Stephen on 17 Jan 2018
Why not do EXACTLY what the error message advises you to do?
Read this to know the difference between ^ and .^:

Elias Gule on 17 Jan 2018
Let's say for example you have the vector:
t = 1 : 10;
This is basically a 1-by-10 matrix. So,
t^2
tries to perform the matrix multiplication operation; but t is 1x10, hence the inner dimensions of t*t are not the same. That is why you get an error.
Now if what you actually want is an array of squares of elements of t, then
t.^2
is the what you must use. So you equation should be :
y = 1./(t*(3/10^(8*8)*10^(3/2))/2 + 1).^(2/3);
Note: ./, .* and .^ are element-wise operators.
Duong Nguyen on 17 Jan 2018
Thank you for your explanation. I have just studied MATLAB for a week so I do not understand it fully. It is a really helpful comment.