Math & Science ⇒ combining \frac and \sum

[dkeeble]

Hi,

I have an equation that is a fraction with a \sum on the top and no sum on the bottom. Using \left and \right, or \bigl \bigr mean that the delimiters are centred around the line of the fraction - but the sum on top is much higher than the constants on the bottom, so it looks silly. My question thererfore is: Can you adjust the height of the centre of the delimiters with respect to the contained maths? Or, even better, can one change the height of the maths with respect to the delimiters, ie change the height of the centre line from the \frac?

Code: Select all

\chi^2=\left[\displaystyle\frac{\displaystyle\sum_\mathbf{h}{w_\mathbf{h}\left(F_{\mathbf{h}(o)}^2-F_{\mathbf{h}(c)}^2\right)^2}}{N_{\text{R}}-N_{\text{P}}}\right]^{\frac{1}{2}}

[emime]

I'm not sure to understand what you mean with ...
> Can you adjust the height of the centre of the delimiters with respect to the contained maths?

Maybe you want just play with a raisebox.

Code: Select all

\[
\chi^2=\left[\raisebox{-2mm}{$\displaystyle
\dfrac{\displaystyle\sum_\mathbf{h}{w_\mathbf{h}\left(F_{\mathbf{h}(o)}^2-F_{\mathbf{h}(c)}^2\right)^2}}
{N_{\text{R}}-N_{\text{P}}}$}\right]^{\frac{1}{2}}
\]

But more rigorous to have the equal sign aligned with the fraction...so I would move slightly down the denominator only.

Code: Select all

\[
\chi^2=\left[\displaystyle
\dfrac{\displaystyle\sum_\mathbf{h}{w_\mathbf{h}\left(F_{\mathbf{h}(o)}^2-F_{\mathbf{h}(c)}^2\right)^2}}
{\raisebox{-2mm}{$N_{\text{R}}-N_{\text{P}}$}}\right]^{\frac{1}{2}}
\]

Hope it does the trick.

[Juanjo]

Replace the denominator by \rule{0pt}{15pt}N_{\text{R}}-N_{\text{P}} and adjust the height of the invisible rule.

[dkeeble]

Maybe you want just play with a raisebox.

That does exactly what I wanted, thanks!