Does the direction of the contour clockwise/anticlockwise effect the value of the residue?
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Yes a Jordan curve has a specific orientation. – mathreadler Apr 16 '17 at 17:55

@mathreadler's answer is incorrect, a residue is a property of a function and not of contours. See meowmix's answer below. – user217285 Apr 16 '17 at 18:03

It is not an answer but a comment addressing the obviously intended question of the contour affecting the value of integration. Meowmix's answer is excellent though as it addresses both things in a clear and concise manner. – mathreadler Apr 16 '17 at 18:04
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Of course it won't affect the value of the residue, because the residue is determined by a Laurent series expansion around a singularity, and determined solely by the function.
However, the value of a contour integral itself will be affected by the curve's orientation. More generally, if $I(\gamma,a_k)$ is the winding number of your contour $\gamma$ around singularity $a_k$, we get a similar, but more general statement of the residue theorem:
$$\oint f(z) dz = 2\pi i \sum \text{Res}(f, a_k) I(\gamma, a_k)$$
So, specifically, if your contour is reversed, the integral will be negative.
Meow Mix
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If you switch from one to the other, the minus sign is added. It doesn't really matter which is negative. – Meow Mix Apr 16 '17 at 18:00

What I mean is for example the function $\frac{3zz^2}{z}=\frac{3}{z}1z$ has residue equal to $3$. Now If I am asked to take contour clockwise or anticlockwise then which will make it $3$? – gbd Apr 16 '17 at 18:05

The positively oriented curve will always be just $2\pi i$ multiplied by the sum of the residues, because the winding number is always 1. Meanwhile, the negatively oriented curve will be negative, because the winding number is negative. – Meow Mix Apr 16 '17 at 18:07