def roll_multi_result(df: pd.DataFrame, apply_func: callable, window: int, return_col_num: int, **kwargs):
"""
rolling with multiple columns on 2 dim pd.Dataframe
* the result can apply the function which can return pd.Series with multiple columns
call apply function with numpy ndarray
:param return_col_num: apply_func返回的个数（列数）
:param apply_func: --注意：传递的参数，前N个为原index，N=index的维数
:param df: [pd.DataFrame,pd.Series]
:param window: 滚动窗口
:param kwargs:
:return:
"""
# move index to values
v = df.reset_index().values
dim0, dim1 = v.shape
stride0, stride1 = v.strides
stride_values = stride(v, (dim0 - (window - 1), window, dim1), (stride0, stride0, stride1))
result_values = np.full((dim0, return_col_num), np.nan)
for idx, values in enumerate(stride_values, window - 1):
# values : col 1 is index, other is value
result_values[idx,] = apply_func(values, **kwargs)
return result_values
def roll(df: pd.DataFrame, w: int, **kwargs):
"""
Rolling window on dataframe using multiple columns
>>> roll(pd.DataFrame(np.random.randn(10,3), index=list('ABCDEFGHIJ')), 3).apply(print)
or alternatively
>>> pd.DataFrame(np.random.randn(10,3), index=list('ABCDEFGHIJ')).pipe(roll, 3).apply(lambda x: print(x[2]))
:param df: pandas DataFrame
:param w: window size (only integers)
:return: rolling window
"""
if w > len(df):
raise ValueError("Window size exceeds number of rows !")
v = df.values
d0, d1 = v.shape
s0, s1 = v.strides
a = stride(v, (d0 - (w - 1), w, d1), (s0, s0, s1))
rolled_df = pd.concat({
row: pd.DataFrame(values, columns=df.columns)
for row, values in zip(df.index, a)
})
return rolled_df.groupby(level=0, **kwargs)
def roll(df, w, **kwargs):
v = df.values
d0, d1 = v.shape
s0, s1 = v.strides
a = stride(v, (d0 - (w - 1), w, d1), (s0, s0, s1))
rolled_df = pd.concat({
row: pd.DataFrame(values, columns=df.columns)
for row, values in zip(df.index, a)
})
return rolled_df.groupby(level=0, **kwargs)
def makeS(full, train, var):
"""
Given 2 dataframes, "train" which is a subset of "full" used to train a
model, and a variable name, makes a new matrix of a row length(n) equal to
the row length of the training data frame and a column length(m) equal to
the row length of the full data frame. Each column is a repeat of the
values of the selected variable from the training data frame. The new
matrix created however only takes up the memory space of what a single
column does.
"""
ncol = len(full)
vec = train[var].values
return stride(vec, shape=(len(vec), ncol), strides=(vec.itemsize, 0))
def roll(df, w, **kwargs):
# returns iterable of DataFrames each having some length (for window-type functions)
v = df.values
d0, d1 = v.shape
s0, s1 = v.strides
a = stride(v, (d0 - (w - 1), w, d1), (s0, s0, s1))
if len(a) == 0:
return np.array([])
rolled_df = pd.concat({
row: pd.DataFrame(values, columns=df.columns)
for row, values in zip(df.index, a)
})
return rolled_df.groupby(level=0, **kwargs)
def roll(df, w, **kwargs):
""" Helper function to apply rolling calculation to multiple columns """
v = df.values
d0, d1 = v.shape
s0, s1 = v.strides
a = stride(v, (d0 - (w - 1), w, d1), (s0, s0, s1))
rolled_df = pd.concat({
row: pd.DataFrame(values, columns=df.columns)
for row, values in zip(df.index, a)
})
return rolled_df.groupby(level=0, **kwargs)
def roll(df, w, **kwargs):
"""
Roll a df.
Input: df -> df to be rolled
w -> the length of the rolling window
"""
v = df.values
d0, d1 = v.shape
s0, s1 = v.strides
a = stride(v, (d0 - (w - 1), w, d1), (s0, s0, s1))
rolled_df = pd.concat({
row: pd.DataFrame(values, columns=df.columns)
for row, values in zip(df.index, a)
})
return rolled_df.groupby(level=0, **kwargs)
def _transform_all_data(self):
self._log.debug("transforming NGSIM data")
df = pd.read_csv(
self._path,
sep=r"\s+",
header=None,
names=(
"vehicle_id",
"frame_id", # 1 frame per .1s
"total_frames",
"global_time", # msecs
# front center in feet from left lane edge
"position_x" if not self._swap_xy else "position_y",
# front center in feet from entry edge
"position_y" if not self._swap_xy else "position_x",
"global_x" if not self._swap_xy else "global_y", # front center in feet
"global_y" if not self._swap_xy else "global_x", # front center in feet
"length", # feet
"width", # feet
"type", # 1 = motorcycle, 2 = auto, 3 = truck
"speed", # feet / sec
"acceleration", # feet / sec^2
"lane_id", # lower is further left
"preceding_vehicle_id",
"following_vehicle_id",
"spacing", # feet
"headway", # secs
),
)
df["sim_time"] = df["global_time"] - min(df["global_time"])
# offset of the map from the data...
x_offset = self._dataset_spec.get("x_offset_px", 0) / self.scale
y_offset = self._dataset_spec.get("y_offset_px", 0) / self.scale
df["length"] *= METERS_PER_FOOT
df["width"] *= METERS_PER_FOOT
df["speed"] *= METERS_PER_FOOT
df["acceleration"] *= METERS_PER_FOOT
df["spacing"] *= METERS_PER_FOOT
df["position_y"] *= METERS_PER_FOOT
# SMARTS uses center not front
df["position_x"] = (
df["position_x"] * METERS_PER_FOOT - 0.5 * df["length"] - x_offset
)
if y_offset:
df["position_x"] = df["position_y"] - y_offset
if self._flip_y:
max_y = self._dataset_spec["map_net"]["max_y"]
df["position_y"] = (max_y / self.scale) - df["position_y"]
# Use moving average to smooth positions...
df.sort_values("sim_time", inplace=True) # just in case it wasn't already...
k = 15 # kernel size for positions
for vehicle_id in set(df["vehicle_id"]):
same_car = df["vehicle_id"] == vehicle_id
df.loc[same_car, "position_x"] = (
df.loc[same_car, "position_x"]
.rolling(window=k)
.mean()
.shift(1 - k)
.values
)
df.loc[same_car, "position_y"] = (
df.loc[same_car, "position_y"]
.rolling(window=k)
.mean()
.shift(1 - k)
.values
)
# and compute heading with (smaller) rolling window (=3) too..
v = df.loc[same_car, ["position_x", "position_y"]].shift(1).values
d0, d1 = v.shape
s0, s1 = v.strides
headings = [
self._cal_heading(values)
for values in stride(v, (d0 - 2, 3, d1), (s0, s0, s1))
]
df.loc[same_car, "heading_rad"] = headings + [headings[-1], headings[-1]]
# ... and new speeds (based on these smoothed positions)
# (This also overcomes problem that NGSIM speeds are "instantaneous"
# and so don't match with dPos/dt, which can affect some models.)
speeds = [
self._cal_speed(values)
for values in stride(v, (d0 - 2, 3, d1), (s0, s0, s1))
]
df.loc[same_car, "speed_discrete"] = speeds + [None, None]
map_width = self._dataset_spec["map_net"].get("width")
if map_width:
valid_x = (df["position_x"] * self.scale).between(0, map_width)
df = df[valid_x]
return df
def _transform_all_data(self):
self._log.debug("transforming NGSIM data")
cols = (
"vehicle_id",
"frame_id", # 1 frame per .1s
"total_frames",
"global_time", # msecs
# front center in feet from left lane edge
"position_x" if not self._swap_xy else "position_y",
# front center in feet from entry edge
"position_y" if not self._swap_xy else "position_x",
"global_x"
if not self._swap_xy else "global_y", # front center in feet
"global_y"
if not self._swap_xy else "global_x", # front center in feet
"length", # feet
"width", # feet
"type", # 1 = motorcycle, 2 = auto, 3 = truck
"speed", # feet / sec
"acceleration", # feet / sec^2
"lane_id", # lower is further left
"preceding_vehicle_id",
"following_vehicle_id",
"spacing", # feet
"headway", # secs
)
if self._dataset_spec.get("source") == "NGSIM2":
extra_cols = (
"origin_zone",
"destination_zone",
"intersection",
"section",
"direction",
"movement",
)
cols = cols[:16] + extra_cols + cols[16:]
df = pd.read_csv(self._path, sep=r"\s+", header=None, names=cols)
df["sim_time"] = df["global_time"] - min(df["global_time"])
# offset of the map from the data...
x_margin = self._dataset_spec.get("x_margin_px", 0) / self.scale
y_margin = self._dataset_spec.get("y_margin_px", 0) / self.scale
df["length"] *= METERS_PER_FOOT
df["width"] *= METERS_PER_FOOT
df["speed"] *= METERS_PER_FOOT
df["acceleration"] *= METERS_PER_FOOT
df["spacing"] *= METERS_PER_FOOT
df["position_x"] *= METERS_PER_FOOT
df["position_y"] *= METERS_PER_FOOT
if x_margin:
df["position_x"] = df["position_x"] - x_margin
if y_margin:
df["position_x"] = df["position_y"] - y_margin
if self._flip_y:
max_y = self._dataset_spec["map_net"]["max_y"]
df["position_y"] = (max_y / self.scale) - df["position_y"]
# Use moving average to smooth positions...
df.sort_values("sim_time",
inplace=True) # just in case it wasn't already...
k = 15 # kernel size for positions
for vehicle_id in set(df["vehicle_id"]):
same_car = df["vehicle_id"] == vehicle_id
df.loc[same_car,
"position_x"] = (df.loc[same_car, "position_x"].rolling(
window=k).mean().shift(1 - k).values)
df.loc[same_car,
"position_y"] = (df.loc[same_car, "position_y"].rolling(
window=k).mean().shift(1 - k).values)
# and compute heading with (smaller) rolling window (=3) too..
shift = int(self._heading_window / 2)
pad = self._heading_window - shift - 1
v = df.loc[same_car, ["position_x", "position_y", "speed"]].values
v = np.insert(v, 0, [[np.nan, np.nan, np.nan]] * shift, axis=0)
headings = [
self._cal_heading(values)
for values in sliding_window_view(v, (self._heading_window, 3))
]
df.loc[same_car, "heading_rad"] = headings + [headings[-1]] * pad
# ... and new speeds (based on these smoothed positions)
# (This also overcomes problem that NGSIM speeds are "instantaneous"
# and so don't match with dPos/dt, which can affect some models.)
v = df.loc[same_car, ["position_x", "position_y"]].shift(1).values
d0, d1 = v.shape
s0, s1 = v.strides
speeds = [
self._cal_speed(values)
for values in stride(v, (d0 - 2, 3, d1), (s0, s0, s1))
]
df.loc[same_car, "speed_discrete"] = speeds + [None, None]
# since SMARTS' positions are the vehicle centerpoints, but NGSIM's are at the front,
# now adjust the vehicle position to its centerpoint based on its angle (+y = 0 rad)
df["position_x"] = df["position_x"] - 0.5 * df["length"] * np.cos(
df["heading_rad"] + 0.5 * math.pi)
df["position_y"] = df["position_y"] - 0.5 * df["length"] * np.sin(
df["heading_rad"] + 0.5 * math.pi)
map_width = self._dataset_spec["map_net"].get("width")
if map_width:
valid_x = (df["position_x"] * self.scale).between(
df["length"] / 2, map_width - df["length"] / 2)
df = df[valid_x]
return df
