merlin.timeseries

merlin.timeseries.add_dates(dates, dods, key='dates')

Inserts dates into each subdictionary of the parent dictionary.

Parameters:

• dod – A dictionary of dictionaries
• dates – A sequence of dates
• key – Subdict key where dates values is inserted

Returns:

An updated dictionary of dictionaries with

merlin.timeseries.create(point, chips_url, acquired, queries, chips_fn=<function get>, dates_fn=<function symmetric_dates>, format_fn=<function pyccd_format>, specs_fn=<function get>)

Queries data, performs date filtering/checking and formats the results.

Parameters:

• point – Tuple of (x, y) which is within the extents of a chip
• chips_url – URL to the chips host:port/context
• acquired – Date range string as start/end, ISO 8601 date format
• queries – dict of URL queries to retrieve chip specs keyed by spectra
• chips_fn – Function that accepts x, y, acquired, url, ubids and returns chips.
• dates_fn – Function that accepts dict of {spectra: [specs],[chips]} and returns a sequence of dates that should be included in the time series. May raise an Exception to halt time series construction.
• format_fn – Function that accepts chip_x, chip_y, chip_locations, chips_and_specs, dates and returns it’s representation of a time series.
• specs_fn – Function that accepts a url query and returns chip specs

Returns:

Return value from format_fn

merlin.timeseries.errorhandler(msg='', raises=False)

Constructs, logs and raises error messages

Parameters:

• msg – Custom message string
• raises – Whether to raise an exception or not

Returns:

exception handler function

merlin.timeseries.identify(chip_x, chip_y, rod)

Adds chip ids (chip_x, chip_y) to the key for each dict entry

Parameters:

• chip_x – x coordinate that identifies the source chip
• chip_y – y coordinate that identifies the source chip
• rod – dict of (x, y): [values]

Returns:

{(chip_x, chip_y, x, y): [values]}

Return type:

dict

merlin.timeseries.pyccd_format(chip_x, chip_y, chip_locations, chips_and_specs, dates)

Builds inputs for the pyccd algorithm.

Parameters:

• chip_x – x coordinate for chip identifier
• chip_y – y coordinate for chip identifier
• chip_locations – chip shaped 2d array of projection coordinates
• chips_and_specs – {k: [chips],[specs]}
• dates – sequence of chip dates to be included in output

Returns:

A tuple of tuples.

Description:

The pyccd format requires a key of (chip_x, chip_y, x, y) with a dictionary of sorted numpy arrays representing each spectra plus an additional sorted dates array.

>>> pyccd_format(*args)
(((chip_x, chip_y, x1, y1), {"dates": [],  "reds": [],
                             "greens": [], "blues": [],
                             "nirs1": [],  "swir1s": [],
                             "swir2s": [], "thermals": [],
                             "quality": []}),
 ((chip_x, chip_y, x1, y2), {"dates": [],  "reds": [],
                             "greens": [], "blues": [],
                             "nirs1": [],  "swir1s": [],
                             "swir2s": [], "thermals": [],
                             "quality": []}))
...

merlin.timeseries.refspec(cas)

Returns the first chip spec from the first key to use as a reference.

Parameters:cas – chips and specs {key: [chips],[specs]} Returns:chip spec Return type:dict

merlin.timeseries.sort(chips, key=<function <lambda>>)

Sorts all the returned chips by date.

Parameters:chips – sequence of chips Returns:sorted sequence of chips

merlin.timeseries.symmetric_dates(dates)

Returns a sequence of dates for chips that should be included in downstream functions. May raise Exception.

Parameters:dates – {key: [datestrings,]} Returns:Sequence of date strings or Exception

Example

>>> symmetrical_dates({"red":  [ds3, ds1, ds2],
                       "blue": [ds2, ds3, ds1]})
[2, 3, 1]
>>>
>>> symmetrical_dates({"red":  [ds3, ds1],
                       "blue": [ds2, ds3, ds1]})
Exception: red:[3, 1] does not match blue:[2, 3, 1]