def _apply_raw(df):
"""
df:
| Start time | End time | device_name
------------------------------------------
| ts1 | ts2 | name1
return df:
| time | dev_1 | .... | dev_n |
--------------------------------
| ts1 | 1 | .... | 0 |
"""
# change to rep3
df_dev = device_rep1_2_rep3(df)
dev_lst = df_dev[DEVICE].unique()
# create raw dataframe
df_res = _create_devices(dev_lst, index=df_dev[TIME])
# create first row in dataframe
df_res.iloc[0] = np.zeros(len(dev_lst))
col_idx = np.where(dev_lst == df_dev.iloc[0].device)[0][0]
df_res.iloc[0, col_idx] = 1
# update all rows of the dataframe
for i, row in enumerate(df_dev.iterrows()):
if i == 0: continue
#copy previous row into current and update current value
df_res.iloc[i] = df_res.iloc[i - 1].values
col_idx = np.where(dev_lst == df_dev.iloc[i].device)[0][0]
df_res.iloc[i, col_idx] = int(df_dev.iloc[i].val)
return df_res
def duration_correlation(df):
""" compute the crosscorelation by comparing for every interval the binary values
between the devices
Parameters
----------
df_dev: pd.DataFrame
device representation 1
returns
-------
pd.DataFrame (k x k)
crosscorrelation between each device
"""
df_dev = device_rep1_2_rep3(df)
dev_lst = df_dev['device'].unique()
df_dev = df_dev.sort_values(by='time')
K = len(dev_lst)
crosstab = np.full((K, K), 0, dtype='timedelta64[ns]')
# make off to -1 and on to 1 and then calculate cross correlation between signals
states = np.full(K, -1)
prae_time = df_dev.iloc[0].time
dev_idx = np.where(dev_lst == df_dev.iloc[0].device)[0][0]
states[dev_idx] = 1
# sweep through all
i = 0
for row in df_dev.iterrows():
if i == 0:
i += 1
continue
# for every device determine cross correlation by multiplying
# the state of the device with the vector of states in order
# to know if to subtract or add the time in the previous interval
nt = row[1].time
td = (nt - prae_time).to_timedelta64()
for j in range(K):
dev_st = states[j]
tdiffs = dev_st * states * td
crosstab[j, :] = crosstab[j, :] + tdiffs
# update state array with new state and set new time
dev_idx = np.where(dev_lst == row[1].device)[0][0]
if row[1].val:
states[dev_idx] = 1
else:
states[dev_idx] = -1
prae_time = nt
# normalize by the whole time. Diagonal contains full timeframe
crosstab = crosstab / crosstab[0, 0]
ct = pd.DataFrame(data=crosstab, index=dev_lst, columns=dev_lst)
return ct
def create_raw(df_devices, t_res=None, sample_strat='ffill', idle=False):
dev = df_devices.copy()
raw = _apply_raw(dev)
dev = device_rep1_2_rep3(dev)
if t_res is not None:
raw = _resample_df(raw, t_res, dev=dev, sample_strat=sample_strat)
return raw
def create_changepoint(df_devices, t_res=None, idle=False):
dev = df_devices.copy()
dev = device_rep1_2_rep3(dev)
cp = _apply_changepoint(dev)
if t_res is not None:
resampler = cp.resample(t_res, kind='timestamp')
cp = resampler.apply(_cp_evaluator, dev=dev)
return cp
def create_lastfired(df_devices, t_res=None):
dev = df_devices.copy()
dev = device_rep1_2_rep3(dev)
lf = _apply_changepoint(dev)
if t_res is not None:
resampler = lf.resample(t_res, kind='timestamp')
lf = resampler.apply(_lf_evaluator, df=lf.copy())
lf = lf.fillna(method='ffill')
return lf
def device_tcorr(df, t_windows=['20s']):
""" computes for every time window the prevalence of device triggers
for each device
Parameters
----------
df : pd.DataFrame
device representation 1
t_windows : list
time frames or a single window (string)
Returns
-------
lst : list of panda dataframes
"""
t_windows = timestr_2_timedeltas(t_windows)
df = device_rep1_2_rep3(df)
# create timediff to the previous trigger
df['time_diff'] = df['time'].diff()
#knn
# do cumsum for row_duration
# for each row mask the rows that fall into the given area
dev_list = df.device.unique()
df.iloc[0, 3] = pd.Timedelta(0, 's')
df['cum_sum'] = df['time_diff'].cumsum()
lst = []
for t_window in t_windows:
# create cross table with zeros
res_df = pd.DataFrame(columns=dev_list, index=dev_list)
for col in res_df.columns:
res_df[col].values[:] = 0
# this whole iterations can be done in parallel
for row in df.iterrows():
td = row[1].cum_sum
dev_name = row[1].device
df['tmp'] = (td - t_window < df['cum_sum']) & (df['cum_sum'] <
td + t_window)
tmp = df.groupby('device')['tmp'].sum()
res_df.loc[dev_name] += tmp
lst.append(res_df)
return lst
def _create_index(self, df_devices, t_res):
"""
create the dummy dataframe for the index from the devices
index | val
"""
df = device_rep1_2_rep3(df_devices.copy())
df = df.pivot(index='time', columns='device', values='val').iloc[:, :1]
df = df.astype(bool) # just to have a lower memory footprint
# resample with frequency
resampler = df.resample(t_res, kind='timestamp')
df_index = resampler.sum()
df_index.columns = ['val']
df_index['val'] = 1
return df_index
def device_triggers_one_day(df, t_res='1h'):
"""
computes the amount of triggers of a device for each hour of a day summed
over all the weeks
params: df: pd.DataFrame
repr2 of devices
t_res: [0,24]h or [0,60]m for a resoltion in hours, minutes
returns: df
index: hours
columsn devices
values: the amount a device changed states
"""
df = device_rep1_2_rep3(df)
# compute new table
df['time'] = df['time'].apply(time2int, args=[t_res])
df = df.groupby(['time', 'device']).sum().unstack()
df = df.fillna(0)
df.columns = df.columns.droplevel(0)
return df
