Difference between revisions of "Talk:Extra:Intersecting planes"
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+ | ==Rotate <math>\mathbf{v}_{2b}</math> about <math>\mathbf{n}_{1}</math>== | ||
+ | In general, rotation of a vector <math>\scriptstyle | ||
+ | \mathbf{v}_{\mathrm{start}} = \begin{bmatrix} x & y & z \end{bmatrix}</math>about an arbitrary unit-vector <math>\scriptstyle | ||
+ | \mathbf{n} = \begin{bmatrix} u & v & w \end{bmatrix}</math> gives ([https://en.wikipedia.org/wiki/Rotation_matrix#Rotation_matrix_from_axis_and_angle 1], [http://inside.mines.edu/fs_home/gmurray/ArbitraryAxisRotation/ 2]): | ||
+ | ::<math> | ||
+ | \mathbf{v}_{\mathrm{end}} = \begin{bmatrix} u(ux +vy+wz)(1-\cos \theta) + x \cos \theta + (-wy+vz)\sin \theta \\ | ||
+ | v(ux+vy+wz)(1 - \cos \theta) + y \cos \theta + (wx-uz) \sin \theta\\ | ||
+ | w(ux+vy+wz)(1-\cos \theta) + z \cos \theta + (-vx+uy) \sin \theta \end{bmatrix} | ||
+ | </math> | ||
+ | In this particular case, we thus expect: | ||
+ | ::<math> | ||
+ | \begin{alignat}{2} | ||
+ | \mathbf{v}_{2} & = \begin{bmatrix} -y\sin \phi \\ | ||
+ | y \cos \phi \\ | ||
+ | z(1-\cos \phi) + z \cos \phi\end{bmatrix} | ||
+ | \\ | ||
+ | & = \begin{bmatrix} -q \cos \alpha\sin \phi \\ | ||
+ | q \cos \alpha \cos \phi \\ | ||
+ | q \sin \alpha(1-\cos \phi) + q \sin \alpha \cos \phi\end{bmatrix} | ||
+ | \\ | ||
+ | & = q \begin{bmatrix} - \cos \alpha\sin \phi \\ | ||
+ | \cos \alpha \cos \phi \\ | ||
+ | \sin \alpha\end{bmatrix} | ||
+ | \end{alignat} | ||
+ | </math> | ||
+ | |||
+ | |||
==Rotate <math>\mathbf{v}_{2b}</math> about <math>\mathbf{n}_{2}</math>== | ==Rotate <math>\mathbf{v}_{2b}</math> about <math>\mathbf{n}_{2}</math>== | ||
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\cos\alpha \cos \phi \\ | \cos\alpha \cos \phi \\ | ||
\sin\alpha \cos \phi\end{bmatrix} | \sin\alpha \cos \phi\end{bmatrix} | ||
+ | \end{alignat} | ||
+ | </math> | ||
+ | |||
+ | |||
+ | ==Generalized distance between two vectors== | ||
+ | '''Warning: Errors below''' (this is just intermediate/working stuff) | ||
+ | |||
+ | Imagine [[reciprocal-space]] [[scattering]] that is a ring; more specifically a pseudo-toroid with Gaussian-like decay. The intensity overall is: | ||
+ | ::<math> | ||
+ | I = \exp \left [ -(q_{rr}-q_0)^2/(2 \sigma_q^2) \right ] \exp \left [ -q_{rz}^2/(2 \sigma_q^2) \right ] | ||
+ | </math> | ||
+ | Where we use the subscript ''r'' to denote the reciprocal-space coordinate system, and <math>\scriptstyle q_{rr} = \sqrt{q_{rx}^2+q_{ry}^2}</math>. The plane of the [[detector]] (i.e. the [[Ewald sphere|Ewald plane]]) is denoted by ''d'': | ||
+ | ::<math> | ||
+ | \mathbf{v}_{d} = \begin{bmatrix} q_{dx} & q_{dy} & 0 \end{bmatrix} | ||
+ | </math> | ||
+ | We set the symmetry axis in realspace (detector coordinate system) to be the <math>\scriptstyle x</math>-axis. The reciprocal-space is tilted by <math>\scriptstyle \chi_0</math> (about the <math>\scriptstyle y</math>-axis), before the 'powder' rotation about the <math>\scriptstyle x</math>-axis (where <math>\scriptstyle \alpha</math> goes from <math>\scriptstyle -\pi</math> to <math>\scriptstyle +\pi</math>). Consider an initial vector: | ||
+ | ::<math> | ||
+ | \mathbf{v}_{d0} = \begin{bmatrix} q \sin \phi & q \cos \phi & 0 \end{bmatrix} | ||
+ | </math> | ||
+ | The 1st rotation (about <math>\scriptstyle y</math>-axis by <math>\scriptstyle \chi_0</math>) involves: | ||
+ | ::<math> | ||
+ | \begin{alignat}{2} | ||
+ | \mathbf{v}_{d1} & = R_y(\chi_0) \mathbf{v}_{d0} \\ | ||
+ | & = \begin{bmatrix} | ||
+ | \cos \chi_0 & 0 & \sin \chi_0 \\ | ||
+ | 0 & 1 & 0 \\ | ||
+ | -\sin \chi_0 & 0 & \cos \chi_0 \\ | ||
+ | \end{bmatrix} | ||
+ | \begin{bmatrix} | ||
+ | q \sin \phi \\ | ||
+ | q \cos \phi \\ | ||
+ | 0 \\ | ||
+ | \end{bmatrix} \\ | ||
+ | & = \begin{bmatrix} | ||
+ | q \sin \phi \cos \chi_0 \\ | ||
+ | q \cos \phi \\ | ||
+ | - q \sin \phi \sin \chi_0 \\ | ||
+ | \end{bmatrix} | ||
+ | \end{alignat} | ||
+ | </math> | ||
+ | Consider a 2nd rotation around the vector (normal to the detector plane) ('''Warning: This is erroneous since the alpha rotation is just another phi rotation.'''): | ||
+ | ::<math> | ||
+ | \begin{alignat}{2} | ||
+ | \mathbf{n}_{d1} & = R_y(\chi_0) \mathbf{n}_{d0} \\ | ||
+ | & = \begin{bmatrix} | ||
+ | \cos \chi_0 & 0 & \sin \chi_0 \\ | ||
+ | 0 & 1 & 0 \\ | ||
+ | -\sin \chi_0 & 0 & \cos \chi_0 \\ | ||
+ | \end{bmatrix} | ||
+ | \begin{bmatrix} | ||
+ | 0 \\ | ||
+ | 0 \\ | ||
+ | 1 \\ | ||
+ | \end{bmatrix} \\ | ||
+ | & = \begin{bmatrix} | ||
+ | \sin \chi_0 \\ | ||
+ | 0 \\ | ||
+ | \cos \chi_0 \\ | ||
+ | \end{bmatrix} | ||
+ | \end{alignat} | ||
+ | </math> | ||
+ | So the second rotation yields: | ||
+ | ::<math> | ||
+ | \begin{alignat}{2} | ||
+ | \mathbf{v}_{d2} & = | ||
+ | \begin{bmatrix} u(ux +wz)(1-\cos \alpha) + x \cos \alpha + -wy \sin \alpha \\ | ||
+ | y \cos \alpha + (wx-uz) \sin \alpha\\ | ||
+ | w(ux+wz)(1-\cos \alpha) + z \cos \alpha + uy \sin \alpha \end{bmatrix} \\ | ||
+ | & = | ||
+ | \begin{bmatrix} \sin \chi_0 (\sin \chi_0 q \sin \phi \cos \chi_0 - \cos \chi_0 q \sin \phi \sin \chi_0)(1-\cos \alpha) + q \sin \phi \cos \chi_0 \cos \alpha + - \cos \chi_0 q \cos \phi \sin \alpha \\ | ||
+ | q \cos \phi \cos \alpha + (\cos \chi_0 q \sin \phi \cos \chi_0 + \sin \chi_0 q \sin \phi \sin \chi_0) \sin \alpha\\ | ||
+ | \cos \chi_0(\sin \chi_0 q \sin \phi \cos \chi_0 - \cos \chi_0 q \sin \phi \sin \chi_0)(1-\cos \alpha) + - q \sin \phi \sin \chi_0 \cos \alpha + \sin \chi_0 q \cos \phi \sin \alpha \end{bmatrix} \\ | ||
+ | & = | ||
+ | q \begin{bmatrix} \sin^2 \chi_0 \sin \phi (\cos \chi_0 - \cos \chi_0 )(1-\cos \alpha) + \sin \phi \cos \chi_0 \cos \alpha - \cos \chi_0 \cos \phi \sin \alpha \\ | ||
+ | \cos \phi \cos \alpha + \sin \phi (\cos^2 \chi_0 + \sin^2 \chi_0 ) \sin \alpha\\ | ||
+ | \cos \chi_0 \sin \chi_0 \sin \phi (\cos \chi_0 - \cos \chi_0 )(1-\cos \alpha) - \sin \phi \sin \chi_0 \cos \alpha + \sin \chi_0 \cos \phi \sin \alpha \end{bmatrix} \\ | ||
+ | |||
+ | & = | ||
+ | q \begin{bmatrix} \cos \chi_0 ( \sin \phi \cos \alpha - \cos \phi \sin \alpha ) \\ | ||
+ | \cos \phi \cos \alpha + \sin \phi \sin \alpha\\ | ||
+ | -\sin \chi_0 ( \sin \phi \cos \alpha - \cos \phi \sin \alpha ) \end{bmatrix} \\ | ||
+ | |||
\end{alignat} | \end{alignat} | ||
</math> | </math> |
Latest revision as of 17:26, 23 December 2015
Rotate Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \mathbf{v}_{2b}} about Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \mathbf{n}_{1}}
In general, rotation of a vector Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \scriptstyle \mathbf{v}_{\mathrm{start}} = \begin{bmatrix} x & y & z \end{bmatrix}} about an arbitrary unit-vector Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \scriptstyle \mathbf{n} = \begin{bmatrix} u & v & w \end{bmatrix}} gives (1, 2):
- Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \mathbf{v}_{\mathrm{end}} = \begin{bmatrix} u(ux +vy+wz)(1-\cos \theta) + x \cos \theta + (-wy+vz)\sin \theta \\ v(ux+vy+wz)(1 - \cos \theta) + y \cos \theta + (wx-uz) \sin \theta\\ w(ux+vy+wz)(1-\cos \theta) + z \cos \theta + (-vx+uy) \sin \theta \end{bmatrix} }
In this particular case, we thus expect:
- Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \begin{alignat}{2} \mathbf{v}_{2} & = \begin{bmatrix} -y\sin \phi \\ y \cos \phi \\ z(1-\cos \phi) + z \cos \phi\end{bmatrix} \\ & = \begin{bmatrix} -q \cos \alpha\sin \phi \\ q \cos \alpha \cos \phi \\ q \sin \alpha(1-\cos \phi) + q \sin \alpha \cos \phi\end{bmatrix} \\ & = q \begin{bmatrix} - \cos \alpha\sin \phi \\ \cos \alpha \cos \phi \\ \sin \alpha\end{bmatrix} \end{alignat} }
Rotate Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \mathbf{v}_{2b}} about Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \mathbf{n}_{2}}
In general, rotation of a vector Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \scriptstyle \mathbf{v}_{\mathrm{start}} = \begin{bmatrix} x & y & z \end{bmatrix}} about an arbitrary unit-vector Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \scriptstyle \mathbf{n} = \begin{bmatrix} u & v & w \end{bmatrix}} gives (1, 2):
- Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \mathbf{v}_{\mathrm{end}} = \begin{bmatrix} u(ux +vy+wz)(1-\cos \theta) + x \cos \theta + (-wy+vz)\sin \theta \\ v(ux+vy+wz)(1 - \cos \theta) + y \cos \theta + (wx-uz) \sin \theta\\ w(ux+vy+wz)(1-\cos \theta) + z \cos \theta + (-vx+uy) \sin \theta \end{bmatrix} }
In this particular case, we thus expect:
- Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \begin{alignat}{2} \mathbf{v}_{2} & = \begin{bmatrix} (-wy+vz)\sin \phi \\ v(vy+wz)(1 - \cos \phi) + y \cos \phi \\ w(vy+wz)(1-\cos \phi) + z \cos \phi\end{bmatrix} \\ & = \begin{bmatrix} (- \cos\alpha q \cos\alpha + -\sin\alpha q \sin\alpha)\sin \phi \\ -\sin\alpha(-\sin\alpha q \cos\alpha+\cos\alpha q \sin\alpha)(1 - \cos \phi) + q \cos\alpha \cos \phi \\ \cos\alpha(-\sin\alpha q \cos\alpha+ \cos\alpha q \sin\alpha)(1-\cos \phi) + q \sin\alpha \cos \phi\end{bmatrix} \\ & = q \begin{bmatrix} -(\cos^2 \alpha +\sin ^2 \alpha)\sin \phi \\ \sin^2 \alpha(\cos\alpha-\cos\alpha )(1 - \cos \phi) + \cos\alpha \cos \phi \\ \cos^2 \alpha(-\sin\alpha + \sin\alpha)(1-\cos \phi) + \sin\alpha \cos \phi\end{bmatrix} \\ & = q \begin{bmatrix} -\sin \phi \\ \cos\alpha \cos \phi \\ \sin\alpha \cos \phi\end{bmatrix} \end{alignat} }
Generalized distance between two vectors
Warning: Errors below (this is just intermediate/working stuff)
Imagine reciprocal-space scattering that is a ring; more specifically a pseudo-toroid with Gaussian-like decay. The intensity overall is:
- Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle I = \exp \left [ -(q_{rr}-q_0)^2/(2 \sigma_q^2) \right ] \exp \left [ -q_{rz}^2/(2 \sigma_q^2) \right ] }
Where we use the subscript r to denote the reciprocal-space coordinate system, and Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \scriptstyle q_{rr} = \sqrt{q_{rx}^2+q_{ry}^2}} . The plane of the detector (i.e. the Ewald plane) is denoted by d:
- Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \mathbf{v}_{d} = \begin{bmatrix} q_{dx} & q_{dy} & 0 \end{bmatrix} }
We set the symmetry axis in realspace (detector coordinate system) to be the Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \scriptstyle x} -axis. The reciprocal-space is tilted by Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \scriptstyle \chi_0} (about the Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \scriptstyle y} -axis), before the 'powder' rotation about the Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \scriptstyle x} -axis (where Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \scriptstyle \alpha} goes from Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \scriptstyle -\pi} to Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \scriptstyle +\pi} ). Consider an initial vector:
- Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \mathbf{v}_{d0} = \begin{bmatrix} q \sin \phi & q \cos \phi & 0 \end{bmatrix} }
The 1st rotation (about Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \scriptstyle y} -axis by Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \scriptstyle \chi_0} ) involves:
- Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \begin{alignat}{2} \mathbf{v}_{d1} & = R_y(\chi_0) \mathbf{v}_{d0} \\ & = \begin{bmatrix} \cos \chi_0 & 0 & \sin \chi_0 \\ 0 & 1 & 0 \\ -\sin \chi_0 & 0 & \cos \chi_0 \\ \end{bmatrix} \begin{bmatrix} q \sin \phi \\ q \cos \phi \\ 0 \\ \end{bmatrix} \\ & = \begin{bmatrix} q \sin \phi \cos \chi_0 \\ q \cos \phi \\ - q \sin \phi \sin \chi_0 \\ \end{bmatrix} \end{alignat} }
Consider a 2nd rotation around the vector (normal to the detector plane) (Warning: This is erroneous since the alpha rotation is just another phi rotation.):
- Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \begin{alignat}{2} \mathbf{n}_{d1} & = R_y(\chi_0) \mathbf{n}_{d0} \\ & = \begin{bmatrix} \cos \chi_0 & 0 & \sin \chi_0 \\ 0 & 1 & 0 \\ -\sin \chi_0 & 0 & \cos \chi_0 \\ \end{bmatrix} \begin{bmatrix} 0 \\ 0 \\ 1 \\ \end{bmatrix} \\ & = \begin{bmatrix} \sin \chi_0 \\ 0 \\ \cos \chi_0 \\ \end{bmatrix} \end{alignat} }
So the second rotation yields:
- Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \begin{alignat}{2} \mathbf{v}_{d2} & = \begin{bmatrix} u(ux +wz)(1-\cos \alpha) + x \cos \alpha + -wy \sin \alpha \\ y \cos \alpha + (wx-uz) \sin \alpha\\ w(ux+wz)(1-\cos \alpha) + z \cos \alpha + uy \sin \alpha \end{bmatrix} \\ & = \begin{bmatrix} \sin \chi_0 (\sin \chi_0 q \sin \phi \cos \chi_0 - \cos \chi_0 q \sin \phi \sin \chi_0)(1-\cos \alpha) + q \sin \phi \cos \chi_0 \cos \alpha + - \cos \chi_0 q \cos \phi \sin \alpha \\ q \cos \phi \cos \alpha + (\cos \chi_0 q \sin \phi \cos \chi_0 + \sin \chi_0 q \sin \phi \sin \chi_0) \sin \alpha\\ \cos \chi_0(\sin \chi_0 q \sin \phi \cos \chi_0 - \cos \chi_0 q \sin \phi \sin \chi_0)(1-\cos \alpha) + - q \sin \phi \sin \chi_0 \cos \alpha + \sin \chi_0 q \cos \phi \sin \alpha \end{bmatrix} \\ & = q \begin{bmatrix} \sin^2 \chi_0 \sin \phi (\cos \chi_0 - \cos \chi_0 )(1-\cos \alpha) + \sin \phi \cos \chi_0 \cos \alpha - \cos \chi_0 \cos \phi \sin \alpha \\ \cos \phi \cos \alpha + \sin \phi (\cos^2 \chi_0 + \sin^2 \chi_0 ) \sin \alpha\\ \cos \chi_0 \sin \chi_0 \sin \phi (\cos \chi_0 - \cos \chi_0 )(1-\cos \alpha) - \sin \phi \sin \chi_0 \cos \alpha + \sin \chi_0 \cos \phi \sin \alpha \end{bmatrix} \\ & = q \begin{bmatrix} \cos \chi_0 ( \sin \phi \cos \alpha - \cos \phi \sin \alpha ) \\ \cos \phi \cos \alpha + \sin \phi \sin \alpha\\ -\sin \chi_0 ( \sin \phi \cos \alpha - \cos \phi \sin \alpha ) \end{bmatrix} \\ \end{alignat} }