def prices_single_prod(prod_id, base_val):
rand = np.random.normal(size=(n_prices,))
#Random times, frequency approximately daily.
delta = np.array([timedelta(r * 5) for r in rand])
times = pd.date_range(start="2000-1-1", periods=n_prices, freq="d")
#TODO: Report Pandas bug "Very odd behavior" ``times + times == times``
times = np.array([pd.Timestamp(t) for t in times]) + delta
#ID string, based on time.
index = [str(t) + "-" + prod_id for t in times]
#Random prices that don't follow the normal distribution
prices = 7 * rand + base_val + np.sin(rand * 3) * 3
#Types, a small amount are observed prices
randu = np.random.uniform(size=n_prices)
types = np.array(["notsold"] * n_prices, dtype=object)
types[randu < 0.6] = "estimated"
types[randu < 0.2] = "observed"
#Realistic pattern for guessed prices
types[[0, 50]] = "guessed"
prices[[0, 50]] = base_val
price_frame = make_price_frame(index=index)
price_frame["id"] = index
price_frame["time"] = times
price_frame["price"] = prices
price_frame["type"] = types
price_frame["product"] = prod_id
#Create mean prices of actually sold items
include = (price_frame["type"] != "notsold") & \
(price_frame["type"] != "guessed")
prices_t = price_frame[include]
prices_t = prices_t.set_index("time")
monthly = pd.TimeGrouper(freq="M")
stats = prices_t.groupby(monthly).aggregate(np.mean)
stats["time"] = stats.index - timedelta(15)
stats["id"] = [str(t) + "-mean-" + prod_id for t in stats["time"]]
stats["product"] = prod_id
stats["type"] = "average"
# print stat
price_frame = price_frame.append(stats, ignore_index=True)
price_frame.set_index("id", drop=False, inplace=True)
return price_frame
def compute_prices(self, listings, products, time_start=None, time_end=None, avg_period="week"):
"""
Compute prices from listings.
Uses linear least square method to compute prices of items that are
sold together with other items. This is equivalent to averaging, to
prices over the listings that were used to compute the prices.
TODO: Delete old prices.
"""
logging.info("Starting to compute prices...")
if avg_period == "week":
offset = pd.datetools.Week(weekday=0)
self.avg_period = "week"
else:
raise NotImplementedError()
# If no start- or end-points are given start or end of listing sequence
# Include listings in incomplete periods at start and end of sequence.
if time_start is None:
time_start = listings["time"].min()
time_start = offset.rollback(time_start)
if time_end is None:
time_end = listings["time"].max()
time_end = offset.rollforward(time_end)
# Create start and end of desired intervals.
intervals = pd.date_range(time_start, time_end, freq=offset)
prices = make_price_frame(0)
# Create list of product IDs. Exclude the place holders the have
# names"xxx-unknown" starting with
product_ids = [p.id for p in products if not p.id.startswith("xxx-unknown")]
if len(product_ids) == 0:
logging.error("Empty product list.")
return prices
# Chop listings into intervals and loop over them.
listings = listings.sort("time")
for i in range(len(intervals) - 1):
intv_start = intervals[i]
intv_end = intervals[i + 1]
offset_mid = timedelta(seconds=(intv_end - intv_start).total_seconds() / 2)
self.average_mid_time = intv_start + offset_mid
intv_listings = listings.ix[(listings["time"] >= intervals[i]) & (listings["time"] < intervals[i + 1])]
logging.debug(
"Interval start: {s}, end: {e}, n listings: {n}.".format(
s=intervals[i], e=intervals[i + 1], n=len(intv_listings)
)
)
if len(intv_listings) == 0:
continue
matrix, listing_prices, listing_ids, product_ids = self.compute_product_occurrence_matrix(
intv_listings, product_ids
)
if matrix.shape[0] == 0:
logging.debug("No valid listing prices.")
continue
product_prices, good_rows, good_cols, problem_products = self.solve_prices_lstsq(
matrix, listing_prices, listing_ids, product_ids
)
intv_prices = self.create_prices_lstsq_soln(
matrix, listing_prices, listing_ids, product_prices, product_ids, good_rows, good_cols, listings
)
prices = prices.append(intv_prices)
return prices
def create_models():
"""
Create a Qt-model-view models for listings, products and tasks.
Additionally returns the related ``DataStore``.
Returns
-------
listings_model, product_model, task_model, price_model, data_store
"""
from clair.qtgui import TaskModel, ProductModel, ListingsModel, PriceModel
from clair.coredata import Product, SearchTask, DataStore, \
make_listing_frame, make_price_frame
fr = make_listing_frame(3)
#All listings need unique ids
fr["id"] = ["eb-110685959294", "eb-111014122908", "eb-457"]
fr["training_sample"] = [1.0, 0.0, nan]
fr["search_tasks"] = ["s-nikon-d90", "s-nikon-d70", "s-nikon-d90"]
fr["expected_products"][0] = ["nikon-d90", "nikon-sb-24"]
fr["expected_products"][1] = ["nikon-d70"]
fr["expected_products"][2] = ["nikon-d90", "nikon-sb-24"]
fr["products"] = [["nikon-d90"], ["nikon-d70"], ["nikon-d90"]]
fr["products_absent"][0] = ["nikon-sb-24"]
fr["thumbnail"][0] = "www.some.site/dir/to/thumb.pg"
fr["image"][0] = "www.some.site/dir/to/img.pg"
fr["title"] = [u"Nikon D90 super duper!", u"Süper Camera", None]
fr["description"][0] = "Buy my old Nikon D90 camera <b>now</b>!"
fr["prod_spec"][0] = {"Marke":"Nikon", "Modell":"D90"}
fr["active"][0] = False
fr["sold"] = [1., 1., 0.]
fr["currency"][0] = "EUR"
fr["price"] = [400., 150, 300]
fr["shipping"][0] = 12.
fr["type"][0] = "auction"
fr["time"] = [datetime(2013,1,10), datetime(2013,2,2), datetime(2013,2,3)]
fr["location"][0] = u"Köln"
fr["postcode"][0] = u"50667"
fr["country"][0] = "DE"
fr["condition"][0] = 0.7
fr["server"][0] = "Ebay-Germany"
fr["server_id"] = ["110685959294", "111014122908", "457"] #ID of listing on server
fr["final_price"][0] = True
# fr["data_directory"] = ""
fr["url_webui"][0] = "www.some.site/dir/to/web-page.html"
# fr["server_repr"][0] = nan
#Put our IDs into index
fr.set_index("id", drop=False, inplace=True, verify_integrity=True)
tasks = [SearchTask("s-nikon-d90", datetime(2000, 1, 1), "ebay-de",
"Nikon D90", "daily", 100, 150, 300, "EUR",
["nikon-d90", "nikon-18-105-f/3.5-5.6--1"]),
SearchTask("s-nikon-d70", datetime(2000, 1, 1), "ebay-de",
"Nikon D70", "daily", 100, 75, 150, "EUR",
["nikon-d70", "nikon-18-105-f/3.5-5.6--1"]),]
products = [Product("nikon-d90", "Nikon D90", "Nikon D90 DSLR camera.",
["Nikon", "D 90"], ["photo.system.nikon.camera",
"photo.camera.system.nikon"]),
Product("nikon-d70", "Nikon D70", "Nikon D70 DSLR camera.",
["Nikon", "D 70"], ["photo.system.nikon.camera",
"photo.camera.system.nikon"])]
pri = make_price_frame(3)
pri["id"] = ["pri-123", "pri-456", "pri-457"]
pri["price"] = [310., 150., 300.]
pri["currency"] = ["EUR", "EUR", "EUR"]
pri["condition"] = [0.7, 0.7, 0.7]
pri["time"] = [datetime(2013,1,10), datetime(2013,2,2), datetime(2013,2,3)]
pri["product"] = ["nikon-d90", "nikon-d70", "nikon-d90"]
pri["listing"] = ["eb-123", "eb-456", "eb-457"]
pri["type"] = ["observed", "observed", "observed"]
pri["avg_period"] = None
pri["avg_num_listings"] = None
conf_dir = relative("../../example-data")
data_store = DataStore(conf_dir, None)
data_store.merge_listings(fr)
data_store.set_products(products)
data_store.add_tasks(tasks)
data_store.merge_prices(pri)
#The models are tested here, creating them may fail.
#Don't break all test, because a single model is broken.
try:
listings_model = ListingsModel()
listings_model.setDataStore(data_store)
except: #IGNORE:W0702
print "Error! ``listings_model`` could not be initialized!"
listings_model = None
try:
task_model = TaskModel()
task_model.setDataStore(data_store)
except: #IGNORE:W0702
print "Error! ``task_model`` could not be initialized!"
task_model = None
try:
product_model = ProductModel()
product_model.setDataStore(data_store)
except: #IGNORE:W0702
print "Error! ``product_model`` could not be initialized!"
product_model = None
try:
price_model = PriceModel()
price_model.setDataStore(data_store)
except: #IGNORE:W0702
print "Error! ``price_model`` could not be initialized!"
price_model = None
return listings_model, product_model, task_model, price_model, data_store
def create_prices_lstsq_soln(
self, matrix, listing_prices, listing_ids, product_prices, product_ids, good_rows, good_cols, listings=None
):
"""
Create product prices from the results of the linear least
square algorithm.
Parameters
----------
matrix : np.array[float]
System matrix of linear least square problem. Each row represents
one listing. each column represents one product. Each entry
represents the condition of a product in a listing. Conditions
range from 1...0.; 1: new, 0.7: used, 0: unusable.
listing_prices : np.array[float]
Prices of listings, constant (known) term of equation system
listing_ids : np.array[basestring]
Listing ID of each matrix's row.
product_prices : np.array[float]
Average price of each product. The solution of the equation system.
product_ids : np.array[basestring]
IDs of the products, represented by elements of `product_prices`
and columns of `matrix`.
good_cols : np.array[bool]
Where `True` prices could be computed by least square algorithm.
good_rows : np.array[bool]
Where `True` listings contain only products whose prices could be
computed by the solution algorithm.
listings : pd.DataFrame
The listings from which the the system of equations was generated.
Will usually contain additional listings.
Returns
-------
prices : pd.DataFrame
The computed prices as a `pd.DataFrame`.
"""
assert matrix.shape[0] == len(listing_prices) == len(listing_ids)
assert matrix.shape[1] == len(product_prices) == len(product_ids)
good_prod_idxs = np.argwhere(good_cols)[:, 0]
# Create the average prices
# Price data is first collected in list of dicts, that is later
# converted to a ``DataFrame``. Each dict is a row of the ``DataFrame``.
prices = make_price_frame(0)
price_data = []
for iprod in range(len(product_prices)):
if iprod not in good_prod_idxs:
continue
single_price_data = {}
# Multiply with condition, solver returns prices for condition "new".
single_price_data["price"] = product_prices[iprod] * self.default_condition
single_price_data["currency"] = self.default_currency
single_price_data["condition"] = self.default_condition
single_price_data["time"] = self.average_mid_time
single_price_data["product"] = product_ids[iprod]
single_price_data["listing"] = u"{}-average".format(self.average_mid_time)
single_price_data["type"] = "average"
single_price_data["avg_period"] = self.avg_period
# Get number of listings that were used for this average price, from
# the system matrix. Count non-zero entries in the price's column.
prod_col = matrix[:, iprod]
prod_col = np.where(prod_col > 0, 1, 0) # Don't count NaNs
n_listings = np.sum(prod_col)
single_price_data["avg_num_listings"] = n_listings
single_price_data["id"] = make_price_id(single_price_data)
price_data.append(single_price_data)
avg_prices = pd.DataFrame(price_data)
prices = prices.append(avg_prices, ignore_index=True, verify_integrity=False)
# Create prices for each item of each listing
# Protect against prices that are NaN
good_prod_prices = np.where(np.isnan(product_prices), 0, product_prices)
# Price data is first collected in list of dicts. Each dict is a price.
price_data = []
for ilist in range(len(listing_prices)):
# Each row of `matrix` represents a listing
row = matrix[ilist, :]
# compute percentage of each product on total listing price
# from average prices.
virt_prod_prices = row * good_prod_prices
list_prod_percent = virt_prod_prices / virt_prod_prices.sum()
# compute price of each item in listing based on these percentages
listing_price = listing_prices[ilist]
list_prod_prices = list_prod_percent * listing_price
# `listings` data frame can be `None` for more easy testing.
if listings is not None:
list_id = listing_ids[ilist]
list_currency = listings.ix[list_id, "currency"]
list_time = listings.ix[list_id, "time"]
else:
list_id = listing_ids[ilist]
list_currency = "Unknown Currency"
list_time = datetime(2000, 1, 1)
prod_idxs = np.argwhere(row > 0)[:, 0]
if len(prod_idxs) == 1:
price_type = "observed"
avg_period = "none"
else:
price_type = "estimated"
avg_period = self.avg_period
# Create a price record for each of the estimated product prices
for iprod in prod_idxs:
if iprod not in good_prod_idxs:
continue
single_price_data = {}
single_price_data["price"] = list_prod_prices[iprod]
single_price_data["currency"] = list_currency
single_price_data["condition"] = row[iprod]
single_price_data["time"] = list_time
single_price_data["product"] = product_ids[iprod]
single_price_data["listing"] = list_id
single_price_data["type"] = price_type
single_price_data["avg_period"] = avg_period
# TODO: Better algorithm, analogous to algorithm above for average prices.
single_price_data["avg_num_listings"] = len(listing_prices)
single_price_data["id"] = make_price_id(single_price_data)
price_data.append(single_price_data)
list_prices = pd.DataFrame(price_data)
prices = prices.append(list_prices, ignore_index=True, verify_integrity=False)
prices.set_index("id", drop=False, inplace=True, verify_integrity=True)
return prices
