# [Tex/LaTex] How to draw a vertical line of desired length in equations.

math-moderulessymbols

I am writing a big formula where a vertical line is needed. Instead of $\vline$ or $|$, does anyone know a way to draw this vertical line of desired length? The formula is something like

$$E\Bigg[ F_{m-1}\Big( \text{some big contents} \Big) |\: \mathcal{F}_1 \Bigg]$$


Thank you very much!

Well, if you are manually defining the size, as in the example you could just put a \Bigg| at the right place. Probably better would be using \left, \middle and \right.
By the way: You should prefer $ and $ instead of double .
$E\left[ F_{m-1}\Big( \text{some big contents} \Big) \middle|\: \mathcal{F}_1 \right]$