def calc(self, data):
"""Calculate averages. Keys (tuples) are converted
into linear indices based on their dimensions
Parameters
----------
data : RDD of (tuple, array) pairs, each array of shape (ncols,)
Data to compute averages from
Returns
-------
ts : array, shape (n, ncols)
"""
dims = getdims(data)
data = subtoind(data, dims.max)
# loop over indices, averaging time series
ts = zeros((self.n, len(data.first()[1])))
for i in range(0, self.n):
if len(self.inds[i]) > 0:
ts[i, :] = self.select(
data, i).map(lambda (k, x): x).sum() / len(self.inds[i])
return ts
def calc(self, data):
"""Calculate averages. Keys (tuples) are converted
into linear indices based on their dimensions
Parameters
----------
data : RDD of (tuple, array) pairs, each array of shape (ncols,)
Data to compute averages from
Returns
-------
self : returns an instance of self.
"""
dims = getdims(data)
data = subtoind(data, dims.max)
# loop over indices, computing average keys and average values
keys = zeros((self.n, len(dims.count())))
values = zeros((self.n, len(data.first()[1])))
for idx, indlist in enumerate(self.inds):
if len(indlist) > 0:
values[idx, :] = self.select(data, idx).map(lambda (k, x): x).sum() / len(indlist)
keys[idx, :] = mean(map(lambda (k, v): k, indtosub(map(lambda k: (k, 0), indlist), dims.max)), axis=0)
self.keys = keys
self.values = values
return self
def calc(self, data):
"""Calculate averages. Keys (tuples) are converted
into linear indices based on their dimensions
Parameters
----------
data : RDD of (tuple, array) pairs, each array of shape (ncols,)
Data to compute averages from
Returns
-------
self : returns an instance of self.
"""
dims = getdims(data)
data = subtoind(data, dims.max)
# loop over indices, computing average keys and average values
keys = zeros((self.n, len(dims.count())))
values = zeros((self.n, len(data.first()[1])))
for idx, indlist in enumerate(self.inds):
if len(indlist) > 0:
values[idx, :] = self.select(
data, idx).map(lambda (k, x): x).sum() / len(indlist)
keys[idx, :] = mean(map(
lambda (k, v): k,
indtosub(map(lambda k: (k, 0), indlist), dims.max)),
axis=0)
self.keys = keys
self.values = values
return self
def test_get_dims_array(self):
subs = [(1, 1, 1), (2, 1, 1), (1, 2, 1), (2, 2, 1), (1, 3, 1), (2, 3, 1),
(1, 1, 2), (2, 1, 2), (1, 2, 2), (2, 2, 2), (1, 3, 2), (2, 3, 2)]
data_local = map(lambda x: (x, array([1.0])), subs)
dims = getdims(data_local)
assert(allclose(dims.max, (2, 3, 2)))
assert(allclose(dims.count(), (2, 3, 2)))
assert(allclose(dims.min, (1, 1, 1)))
def test_get_dims_array(self):
subs = [(1, 1, 1), (2, 1, 1), (1, 2, 1), (2, 2, 1), (1, 3, 1),
(2, 3, 1), (1, 1, 2), (2, 1, 2), (1, 2, 2), (2, 2, 2),
(1, 3, 2), (2, 3, 2)]
data_local = map(lambda x: (x, array([1.0])), subs)
dims = getdims(data_local)
assert (allclose(dims.max, (2, 3, 2)))
assert (allclose(dims.count(), (2, 3, 2)))
assert (allclose(dims.min, (1, 1, 1)))
def calc(self, data):
"""Compute correlation between every data point
and the average of a local neighborhood,
by correlating each data point with the average of a
local neighborhood in x and y (typically time series data)
Parameters
----------
data : RDD of (tuple, array) pairs
The data to compute correlations on
Returns
-------
corr : RDD of (tuple, float) pairs
The local correlation for each record, sorted by keys
"""
def clip(val, mn, mx):
"""Clip a value below by mn and above by mx"""
if val < mn:
return mn
if val > mx:
return mx
else:
return val
def maptoneighborhood(ind, ts, sz, mn, mx):
"""Create a list of key value pairs with multiple shifted copies
of the time series ts over a region specified by sz
"""
rng_x = range(-sz, sz+1, 1)
rng_y = range(-sz, sz+1, 1)
out = list()
for x in rng_x:
for y in rng_y:
new_x = clip(ind[0] + x, mn[0], mx[0])
new_y = clip(ind[1] + y, mn[1], mx[1])
newind = (new_x, new_y, ind[2])
out.append((newind, ts))
return out
# get boundaries using dimension keys
dims = getdims(data)
# flat map to key value pairs where the key is neighborhood identifier and value is time series
neighbors = data.flatMap(lambda (k, v): maptoneighborhood(k, v, self.neighborhood, dims.min[0:2], dims.max[0:2]))
# reduce by key to get the average time series for each neighborhood
means = neighbors.reduceByKey(lambda x, y: x + y).mapValues(lambda x: x / ((2*self.neighborhood+1)**2))
# join with the original time series data to compute correlations
result = data.join(means)
# get correlations
corr = result.mapValues(lambda x: corrcoef(x[0], x[1])[0, 1]).sortByKey()
return corr
def test_get_dims_rdd(self):
subs = [
(1, 1, 1),
(2, 1, 1),
(1, 2, 1),
(2, 2, 1),
(1, 3, 1),
(2, 3, 1),
(1, 1, 2),
(2, 1, 2),
(1, 2, 2),
(2, 2, 2),
(1, 3, 2),
(2, 3, 2),
]
data_local = map(lambda x: (x, array([1.0])), subs)
data = self.sc.parallelize(data_local)
dims = getdims(data)
assert allclose(dims.max, (2, 3, 2))
assert allclose(dims.count(), (2, 3, 2))
assert allclose(dims.min, (1, 1, 1))
def calc(self, data):
"""Calculate averages. Keys (tuples) are converted
into linear indices based on their dimensions
Parameters
----------
data : RDD of (tuple, array) pairs, each array of shape (ncols,)
Data to compute averages from
Returns
-------
ts : array, shape (n, ncols)
"""
dims = getdims(data)
data = subtoind(data, dims.max)
# loop over indices, averaging time series
ts = zeros((self.n, len(data.first()[1])))
for i in range(0, self.n):
ts[i, :] = self.select(data, i).map(lambda (k, x): x).sum() / len(self.inds[i])
return ts
