def extract_trend(inp, cells):
import trend
records = iter(gio.SubboxReader(inp))
meta = records.next()
base_year = meta.yrbeg
name = inp.name
csv_name = name + '.csv'
with open(csv_name, 'w') as csv_out:
csv_file = csv.writer(csv_out)
for record,box in itertools.izip(records, cells):
assert record.first_year == base_year
series = record.series[-360:]
data = [(i//12, v) for i, v in enumerate(series) if v != MISSING]
(a, b, r2) = trend.lm1(data)
csv_file.writerow([id11(box), b])
if b is None:
b = MISSING
else:
b *= 100
yield b, box
def trendlines(data):
"""
Return a a triple of (url,slopelong,slopeshort) for
the full and 30-year trend lines (url is a fragment).
"""
result = Struct()
# full trend
(a,b,r2) = trend.lm1(data)
if a is not None:
yearmin = data[0][0]
yearmax = data[-1][0]
full_left_y = int(round(a + yearmin * b))
full_right_y = int(round(a + yearmax * b))
# thirty-year trend
# Find most recent 30 years of _valid_ data
valid_count = 0
last_valid = -9999 # largest index with valid data
for i,(x,y) in reversed(list(enumerate(data))):
if y is None:
continue
last_valid = max(last_valid, i)
valid_count += 1
if valid_count >= 30:
break
(a_30,b_30,r2_30) = trend.lm1(data[i:])
left_y = int(round(a_30 + (yearmin+i) * b_30))
left_x = -100 + 200*float(i)/(yearmax-yearmin)
right_y = int(round(a_30 + (yearmin+last_valid) * b_30))
right_x = -100 + 200*float(last_valid)/(yearmax-yearmin)
result.urlfrag = ("-100,100|%d,%d|%.0f,%.0f|%d,%d" %
(full_left_y, full_right_y,
left_x, right_x,
left_y, right_y))
result.b_full = b
result.b_short = b_30
result.r2_full = r2
result.r2_short = r2_30
else:
result.b_full = None
result.b_short = None
result.r2_full = None
result.r2_short = None
result.urlfrag = "-999|-999|-999|-999"
return result
def trendlines(data):
"""
Return a a triple of (url,slopelong,slopeshort) for
the full and 30-year trend lines (url is a fragment).
"""
result = Struct()
# full trend
(a, b, r2) = trend.lm1(data)
if a is not None:
yearmin = data[0][0]
yearmax = data[-1][0]
full_left_y = int(round(a + yearmin * b))
full_right_y = int(round(a + yearmax * b))
# thirty-year trend
# Find most recent 30 years of _valid_ data
valid_count = 0
last_valid = -9999 # largest index with valid data
for i, (x, y) in reversed(list(enumerate(data))):
if y is None:
continue
last_valid = max(last_valid, i)
valid_count += 1
if valid_count >= 30:
break
(a_30, b_30, r2_30) = trend.lm1(data[i:])
left_y = int(round(a_30 + (yearmin + i) * b_30))
left_x = -100 + 200 * float(i) / (yearmax - yearmin)
right_y = int(round(a_30 + (yearmin + last_valid) * b_30))
right_x = -100 + 200 * float(last_valid) / (yearmax - yearmin)
result.urlfrag = (
"-100,100|%d,%d|%.0f,%.0f|%d,%d" %
(full_left_y, full_right_y, left_x, right_x, left_y, right_y))
result.b_full = b
result.b_short = b_30
result.r2_full = r2
result.r2_short = r2_30
else:
result.b_full = None
result.b_short = None
result.r2_full = None
result.r2_short = None
result.urlfrag = "-999|-999|-999|-999"
return result
