class Particle(tables.IsDescription):
    name = tables.StringCol(16)
idnumber = tables.Int64Col()
ADCcount = tables.UInt16Col()
TDCcount = tables.UInt8Col()
grid_i = tables.Int32Col()
grid_j = tables.Int32Col()
pressure = tables.Float32Col()
energy = tables.Float64Col()
h5file = tables.openFile('tutorial1.h5', mode='a')
table = h5file.root.detector.readout
particle = table.row
for i in range(10, 20):
    particle['name'] = 'Particle: %6d' % i
particle['TDCcount'] = i % 256
particle['ADCcount'] = i * 256 % (1 << 16)
particle['grid_i'] = i
particle['grid_j'] = 10 - i
particle['pressure'] = float(i * i)
particle['energy'] = float(particle['pressure'] ** 4)
particle['idnumber'] = i * 2 ** 34
particle.append()
h5file.close()
Append data to existing pytables table