# Symbol for vectors with same direction

How do you state that two vectors $\vec{A}$ and $\vec{B}$ have the same direction? I know the symbol $| |$ shows that they are parallel, but is there a symbol like this that shows that the direction of the vectors are equal. I think you would call the two vectors collinear. Is there a symbol to show that two vectors are collinear?

• Is there a reason parallel isn't enough? Because that literally means their directions are exactly the same Oct 18, 2017 at 14:20
• I’m not sure if there’s a symbol for linear dependence (but there may well be one), but to show it you can write $\vec{A}=k\vec{B}$ for some (scalar) constant $k$ Oct 18, 2017 at 14:21
• Generally the word parallel is used for vectors pointing in the same direction, and anti-parallel is used for vectors which are pointing in opposite directions.
– user275377
Oct 18, 2017 at 14:22
• Perhaps he means one vector is a nonnegative scalar multiple of the other. That is: the case of equality for the triangle inequality. Oct 18, 2017 at 14:38
• @aidangallagher4 yeah that's what I ended up using, I was just wondering if there was a better symbol for it. Oct 19, 2017 at 2:40

Not sure if this is considered necrobumping, but my higher level calculus professors in university always used // to notate this. I don't see it anywhere else in the math realm, however.
P.S. Notice though that two vector being collinear does not imply that they are a scalar multiple of each other: e.g., $$\mathbf 0$$ and $$\mathbf k.$$