def lookup_trim(tank, ull, trim_index):
log.info('Starting lookup_trim')
# Called by calc trim corr
# Takes input as tank no /15, ullage, trim, trim index.
# Only deals with 1 trim index, can take mid ullage.
# Negative trim is by the head.
ull_high = []
ull_low = 0
corr_high = []
corr_low = 0
# print('func ~ lookup_trim')
log.debug(('Working with a trim_index of ', trim_index))
log.debug(('Working with a ullage of ', ull))
file = 'tables/trim' + str(tank) + '.csv'
with open(file) as trim_table:
table = csv.reader(trim_table)
for row in table:
index = float(row[0])
# Does the current ullage match the ullage in table.
if index == ull:
log.debug('Ullage is exact match to index collumn')
# Exact ullage match with first column.
# print('Ullage is an exact match.')
x = [row[trim_index]]
x = float(x[0])
return x
else:
log.debug('Ullage is not an exact match')
# Looking for bounding ullages.
if index < ull:
ull_low = index
corr_low = row[trim_index]
log.debug((ull_low, ' < ull_low'))
log.debug((corr_low, ' < corr_low'))
else:
# Higher values than the ullage, adds to list, only takes first value.
ull_high.append(index)
corr_high.append(row[trim_index])
log.debug((ull_high, ' < ull_high'))
log.debug((corr_high, ' , < corr_high'))
corr_low = float(corr_low)
corr_high = float(corr_high[0])
log.debug('Interpolating between corr_high & corr_low')
x = interpolate(ull_low, ull_high[0], corr_low, corr_high, ull)
log.debug(('Interpolated value > ', x))
return x
def calc_trim_corr(tank, ull, trm, trim_index):
log.info('Starting calc_trim_corr')
# Called by __init__
# Rx trim index 1 or 2 figures. 1 is exact match with trim value.
if len(trim_index) == 1:
log.info('Trim is exact match to trim index: Only need to lookup temp_1_t collumn')
trim_index = int(trim_index[0])
corr = lookup_trim(tank, ull, trim_index)
return corr
elif len(trim_index) > 1:
log.info('Trim is not an exact match to trim : Need to interpolate between')
trim_low = trim_index[0]
trim_index_low = trim_index[1]
trim_high = trim_index[2]
trim_index_high = trim_index[3]
corr_low = lookup_trim(tank, ull, trim_index_low)
corr_high = lookup_trim(tank, ull, trim_index_high)
log.debug(('lower index is > %s < high index is > %s <' % (trim_index_low, trim_index_high)))
log.debug(('lower trim is > %s < higher trim is > %s <' % (trim_low, trim_high)))
log.debug(('lower corr is > %s < high corr is > %s <' % (corr_low, corr_high)))
corr = float(interpolate(trim_low, trim_high, corr_low, corr_high, trm))
log.info(('Trim correction calculated at > ', corr))
return corr
