Indexing

                *----------*
               / \        / \
              /   \      /   \
             /     \ gamma    \
            /       *----------*
           /       /  /       /
          /alpha  /  /       /
         *-------/--*       c
          \     /    \beta /
           a   /      \   /
            \ /        \ /
             *-----b----*

  a = 18.36 A
  b = 26.65 A
  c = 4.81 A
  alpha = 90.00 deg
  beta  = 90.00 deg
  gamma = 102.83 deg

  a1 = (18.36, 0.0, 0.0)
  a2 = (5.917873795354449, 25.984635262829016, 0.0)
  a3 = (0.0, 0.0, 4.81)

  b1 = [ 0.05446623 -0.01240442  0.        ]
  b2 = [ 0.          0.03848428  0.        ]
  b3 = [ 0.          0.          0.20790021]

photon energy = 6003.1936 eV
wavelength = 2.0653 A
wave number/Evald radius k = 1/lambda = 0.484187 1/A

def make_lookup_table(b1 = (1.,0.,0.), b2 = (0.,1.,0.), b3 = (0.,0.,1.),\
                      hmax=3, kmax=2, lmax=1, cdtype=np.float32,\
                      evald_rad=3, sigma_q=0.001, fout=None, bpq=None, bpomega=None, bpbeta=None) :
    """Makes lookup table - peak information as a function of angle beta and omega, where
       beta  [deg] - fiber axis tilt,  
       omega [deg] - fiber rotation around axis,  
       For each crysal orientation (beta, gamma) lookup table contains info about lattice nodes
       closest to the Evald's sphere: 
       # beta 20.00  omega 178.50 degree
       # index   beta     omega   h  k  l     dr [1/A]   R(h,k,l)   qv [1/A]   qh [1/A]   P(omega)
         1078    20.00   178.50   1 -5  0     0.000262   0.211944  -0.016779   0.211221   0.964192
         1078    20.00   178.50   0 -1  0     0.002470   0.038484   0.000343   0.038306   0.038686
         1078    20.00   178.50   0  1  0     0.000582   0.038484  -0.000344  -0.038455   0.834544

       where:
       index - orientation index (just an unique integer number)
       beta, omega [deg] - crystal orientation angles,
       h, k, l - Miller indeces
       dr [1/A] - distance between lattice node and Evald's sphere
       R(h,k,l) [1/A] - distance between nodes (h,k,l) and (0,0,0)
       qv, qh [1/A] - vertical and horizontal components of scattering vector q
       P(omega) - un-normalized probability (<1) evaluated for dr(omega) using sigma_q.

       File name is generated automatically with current time stamp like
       lut-cxif5315-r0169-2015-10-23T14:58:36.txt

       Input parameters:
       b1, b2, b3 - reciprocal lattice primitive vectors,
       hmax, kmax, lmax - lattice node indeces
       cdtype - data type for lattice node coordinates,
       evald_rad - Evald's sphere radius,
       sigma_q - expected q resolution,
       fout - open output file object,
       bpq, bpomega, bpbeta - binning parameters for q, omega, and beta
       NOTE: Units of b1, b2, b3, evald_rad, and sigma_q should be the same, for example [1/A].

       Returns 2-d numpy array for image; summed for all beta probobility(omega vs. q_horizontal).
    """

# file name: lut-cxif5315-r0169-2015-10-23T16:03:06.txt

# Triclinic crystal cell parameters:
#   a = 18.36 A
#   b = 26.65 A
#   c = 4.81 A
#   alpha = 90.00 deg
#   beta  = 90.00 deg
#   gamma = 102.83 deg

# 3-d space primitive vectors:
#   a1 = (18.36, 0.0, 0.0)
#   a2 = (5.917873795354449, 25.984635262829016, 0.0)
#   a3 = (0.0, 0.0, 4.81)

# reciprocal space primitive vectors:
#   b1 = [ 0.05446623 -0.01240442  0.        ]
#   b2 = [ 0.          0.03848428  0.        ]
#   b3 = [ 0.          0.          0.20790021]

# photon energy = 6003.1936 eV
# wavelength = 2.0653 A
# wave number/Evald radius k = 1/lambda = 0.484187 1/A
# sigma_q   = 0.000484 1/A (approximately pixel size/sample-to-detector distance = 100um/100mm)
# 3*sigma_q = 0.001453 1/A

# beta 20.00  omega 170.50 degree
# index   beta     omega   h  k  l     dr [1/A]   R(h,k,l)   qv [1/A]   qh [1/A]   P(omega)
  1062    20.00   170.50   0  4  0     0.000595   0.153937  -0.008679  -0.153596   0.469484

# beta 20.00  omega 171.00 degree EMPTY
# beta 20.00  omega 171.50 degree EMPTY
# beta 20.00  omega 172.00 degree
# index   beta     omega   h  k  l     dr [1/A]   R(h,k,l)   qv [1/A]   qh [1/A]   P(omega)
  1065    20.00   172.00   0  3  0    -0.001336   0.115453  -0.005511  -0.115473   0.022208

# beta 20.00  omega 172.50 degree
# index   beta     omega   h  k  l     dr [1/A]   R(h,k,l)   qv [1/A]   qh [1/A]   P(omega)
  1066    20.00   172.50   1 -4  0     0.001294   0.175032  -0.011014   0.174446   0.028162
  1066    20.00   172.50   0  3  0    -0.000396   0.115453  -0.005158  -0.115384   0.715354