def _construct_tensorflow_feed_data(dfs, cube, iter_dims,
nr_of_input_staging_areas):
FD = AttrDict()
# https://github.com/bcj/AttrDict/issues/34
FD._setattr('_sequence_type', list)
# Reference local staging_areas
FD.local = local = AttrDict()
# https://github.com/bcj/AttrDict/issues/34
local._setattr('_sequence_type', list)
# Create placholder variables for source counts
FD.src_ph_vars = AttrDict({
n: tf.placeholder(dtype=tf.int32, shape=(), name=n)
for n in ['nsrc'] + mbu.source_nr_vars()})
# Create placeholder variables for properties
FD.property_ph_vars = AttrDict({
n: tf.placeholder(dtype=p.dtype, shape=(), name=n)
for n, p in cube.properties().iteritems() })
#========================================================
# Determine which arrays need feeding once/multiple times
#========================================================
# Take all arrays flagged as input
input_arrays = [a for a in cube.arrays().itervalues()
if 'input' in a.tags]
src_data_sources, feed_many, feed_once = _partition(iter_dims,
input_arrays)
#=====================================
# Descriptor staging area
#=====================================
local.descriptor = create_staging_area_wrapper('descriptors',
['descriptor'], dfs)
#===========================================
# Staging area for multiply fed data sources
#===========================================
# Create the staging_area for holding the feed many input
local.feed_many = [create_staging_area_wrapper('feed_many_%d' % i,
['descriptor'] + [a.name for a in feed_many], dfs)
for i in range(nr_of_input_staging_areas)]
#=================================================
# Staging areas for each radio source data sources
#=================================================
# Create the source array staging areas
local.sources = { src_nr_var: [
create_staging_area_wrapper('%s_%d' % (src_type, i),
[a.name for a in src_data_sources[src_nr_var]], dfs)
for i in range(nr_of_input_staging_areas)]
for src_type, src_nr_var in source_var_types().iteritems()
}
#======================================
# The single output staging_area
#======================================
local.output = create_staging_area_wrapper('output',
['descriptor', 'model_vis', 'chi_squared'], dfs)
#=================================================
# Create tensorflow variables which are
# fed only once via an assign operation
#=================================================
def _make_feed_once_tuple(array):
dtype = dfs[array.name].dtype
ph = tf.placeholder(dtype=dtype,
name=a.name + "_placeholder")
var = tf.Variable(tf.zeros(shape=(1,), dtype=dtype),
validate_shape=False,
name=array.name)
op = tf.assign(var, ph, validate_shape=False)
#op = tf.Print(op, [tf.shape(var), tf.shape(op)],
# message="Assigning {}".format(array.name))
return FeedOnce(ph, var, op)
# Create placeholders, variables and assign operators
# for data sources that we will only feed once
local.feed_once = { a.name : _make_feed_once_tuple(a)
for a in feed_once }
#=======================================================
# Construct the list of data sources that need feeding
#=======================================================
# Data sources from input staging_areas
src_sa = [q for sq in local.sources.values() for q in sq]
all_staging_areas = local.feed_many + src_sa
input_sources = { a for q in all_staging_areas
for a in q.fed_arrays}
# Data sources from feed once variables
input_sources.update(local.feed_once.keys())
local.input_sources = input_sources
return FD
