# When putting a variety of values in one at a time to an equation it outputs the right answer, but when I put in an array of values the answers are wrong

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I have an equation and a range of values I want to be input into said equation to then make a graph of. The output however gives me a range of y values that are the wrong answers and I can't work out why, but if I equate x to a single number I get the right output. The code looks like as follows:
x = -10:1:10
y = (cos(x)+tanh(x))/x+(x/100)

Paul on 15 Oct 2021
If you want y to be evaluated for each element of x, you need to use the "element-wise" operator ./ (note the dot) instead of /.
x = -10:1:10
x = 1×21
-10 -9 -8 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 8 9 10
y = (cos(x)+tanh(x)) ./ x+(x ./ 100)
y = 1×21
0.0839 0.1223 0.0632 -0.0348 -0.0534 0.0932 0.3732 0.6317 0.6701 0.2113 Inf 1.3119 0.2939 0.0317 0.1264 0.3067 0.3867 0.3206 0.1868 0.0999 0.1161
Simlarly you'd need .* and .^ for element-wise muliplication and exponentiation. The bare / operator is called "mrdivide," which performs a matrix division. Start reading here and follow the documentation to learn more.
Francesca Fernandes on 15 Oct 2021
Oh I should have seen that, thank you