Time Series Metadata Examples
Metadata can be confusing and a daunting task. Hopefully mt_metadata makes it easier. Here we will demonstrate some use cases.
[1]:
from mt_metadata.timeseries import (
Auxiliary, Electric, Experiment, Magnetic, Run, Station, Survey
)
Time Series Metadata as a Single Object
mt_metadata was written so that all metadata can reside under a single object. For example, if you have a single station with multiple runs that have multiple channels, you don’t want to carry around a single file for each. Each level of metadata, namely Experiment, Survey, Station, Run have convenience objects to contain a collection of the next level down. For example Experiment.surveys, Survey.stations or Station.runs or Run.channels. This object is a
combination of a List and Dictionary, which allows the user to access items in the collection by index or key word. Each level of metadata also has a add_, get_, and remove_ method to add/get/remove an item from the collection. And example below.
Tip: The benefit of having the experiment in a single object is later you can populate an MTH5 with out data, just the metadata.
[2]:
experiment = Experiment()
survey_01 = Survey(id="01")
experiment.add_survey(survey_01)
print(experiment.surveys)
Contents:
------------
01 = survey:
citation_dataset.doi = None
citation_journal.doi = None
datum = WGS84
geographic_name = None
id = 01
name = None
northwest_corner.latitude = 0.0
northwest_corner.longitude = 0.0
project = None
project_lead.email = None
project_lead.organization = None
release_license = CC0-1.0
southeast_corner.latitude = 0.0
southeast_corner.longitude = 0.0
summary = None
time_period.end_date = 1980-01-01
time_period.start_date = 1980-01-01
[3]:
experiment.get_survey("01")
[3]:
{
"survey": {
"citation_dataset.doi": null,
"citation_journal.doi": null,
"datum": "WGS84",
"geographic_name": null,
"id": "01",
"name": null,
"northwest_corner.latitude": 0.0,
"northwest_corner.longitude": 0.0,
"project": null,
"project_lead.email": null,
"project_lead.organization": null,
"release_license": "CC0-1.0",
"southeast_corner.latitude": 0.0,
"southeast_corner.longitude": 0.0,
"summary": null,
"time_period.end_date": "1980-01-01",
"time_period.start_date": "1980-01-01"
}
}
[4]:
experiment.surveys[0]
[4]:
{
"survey": {
"citation_dataset.doi": null,
"citation_journal.doi": null,
"datum": "WGS84",
"geographic_name": null,
"id": "01",
"name": null,
"northwest_corner.latitude": 0.0,
"northwest_corner.longitude": 0.0,
"project": null,
"project_lead.email": null,
"project_lead.organization": null,
"release_license": "CC0-1.0",
"southeast_corner.latitude": 0.0,
"southeast_corner.longitude": 0.0,
"summary": null,
"time_period.end_date": "1980-01-01",
"time_period.start_date": "1980-01-01"
}
}
[5]:
experiment.surveys["01"]
[5]:
{
"survey": {
"citation_dataset.doi": null,
"citation_journal.doi": null,
"datum": "WGS84",
"geographic_name": null,
"id": "01",
"name": null,
"northwest_corner.latitude": 0.0,
"northwest_corner.longitude": 0.0,
"project": null,
"project_lead.email": null,
"project_lead.organization": null,
"release_license": "CC0-1.0",
"southeast_corner.latitude": 0.0,
"southeast_corner.longitude": 0.0,
"summary": null,
"time_period.end_date": "1980-01-01",
"time_period.start_date": "1980-01-01"
}
}
Full Experiment
This example demonstrates how to build an experiment from scratch and how to interogate it.
[6]:
experiment = Experiment()
kwargs = {
"time_period.start": "2020-01-01T00:00:00+00:00",
"time_period.end": "2021-01-01T12:00:00+00:00"
}
for survey in ["One", "Two"]:
survey_obj = Survey(id=survey)
survey_obj.filters = {}
for station in ["mt01", "mt02"]:
station_obj = Station(id=station, **kwargs)
for run in ["mt01a", "mt01b"]:
run_obj = Run(id=run, **kwargs)
for ch in ["ex", "ey"]:
ch_obj = Electric(component=ch, **kwargs)
run_obj.add_channel(ch_obj)
for ch in ["hx", "hy", "hz"]:
ch_obj = Magnetic(component=ch, **kwargs)
run_obj.add_channel(ch_obj)
for ch in ["temperature", "voltage"]:
ch_obj = Auxiliary(component=ch, **kwargs)
run_obj.add_channel(ch_obj)
run_obj.update_time_period()
station_obj.runs.append(run_obj)
station_obj.update_time_period()
survey_obj.stations.append(station_obj)
survey_obj.update_time_period()
experiment.surveys.append(survey_obj)
Pick out a channel
To pick out a channel you need to know the survey, station, and run. If you don’t you can figure out what runs, stations, and surveys are available.
[7]:
experiment
[7]:
Experiment Contents
--------------------
Number of Surveys: 2
Survey ID: One
Number of Stations: 2
Number of Filters: 0
--------------------
Station ID: mt01
Number of Runs: 2
--------------------
Run ID: mt01a
Number of Channels: 7
Recorded Channels: ex, ey, hx, hy, hz, temperature, voltage
Start: 2020-01-01T00:00:00+00:00
End: 2021-01-01T12:00:00+00:00
--------------------
Run ID: mt01b
Number of Channels: 7
Recorded Channels: ex, ey, hx, hy, hz, temperature, voltage
Start: 2020-01-01T00:00:00+00:00
End: 2021-01-01T12:00:00+00:00
--------------------
Station ID: mt02
Number of Runs: 2
--------------------
Run ID: mt01a
Number of Channels: 7
Recorded Channels: ex, ey, hx, hy, hz, temperature, voltage
Start: 2020-01-01T00:00:00+00:00
End: 2021-01-01T12:00:00+00:00
--------------------
Run ID: mt01b
Number of Channels: 7
Recorded Channels: ex, ey, hx, hy, hz, temperature, voltage
Start: 2020-01-01T00:00:00+00:00
End: 2021-01-01T12:00:00+00:00
--------------------
Survey ID: Two
Number of Stations: 2
Number of Filters: 0
--------------------
Station ID: mt01
Number of Runs: 2
--------------------
Run ID: mt01a
Number of Channels: 7
Recorded Channels: ex, ey, hx, hy, hz, temperature, voltage
Start: 2020-01-01T00:00:00+00:00
End: 2021-01-01T12:00:00+00:00
--------------------
Run ID: mt01b
Number of Channels: 7
Recorded Channels: ex, ey, hx, hy, hz, temperature, voltage
Start: 2020-01-01T00:00:00+00:00
End: 2021-01-01T12:00:00+00:00
--------------------
Station ID: mt02
Number of Runs: 2
--------------------
Run ID: mt01a
Number of Channels: 7
Recorded Channels: ex, ey, hx, hy, hz, temperature, voltage
Start: 2020-01-01T00:00:00+00:00
End: 2021-01-01T12:00:00+00:00
--------------------
Run ID: mt01b
Number of Channels: 7
Recorded Channels: ex, ey, hx, hy, hz, temperature, voltage
Start: 2020-01-01T00:00:00+00:00
End: 2021-01-01T12:00:00+00:00
--------------------
From an experiment you can access a channel knowing either the index or key word of the survey, station, and run. This is a mix of using index values and keys.
[8]:
ch_ex = experiment.surveys[0].stations["mt01"].runs[0].channels["ex"]
# set some values
ch_ex.dipole_length = 100
ch_ex.measurement_azimuth = 10
ch_ex.negative.x = -50
ch_ex.positive.x = 50
ch_ex.sample_rate = 256
ch_ex
[8]:
{
"electric": {
"channel_number": 0,
"component": "ex",
"data_quality.rating.value": 0,
"dipole_length": 100.0,
"filter.applied": [
false
],
"filter.name": [],
"measurement_azimuth": 10.0,
"measurement_tilt": 0.0,
"negative.elevation": 0.0,
"negative.id": null,
"negative.latitude": 0.0,
"negative.longitude": 0.0,
"negative.manufacturer": null,
"negative.type": null,
"negative.x": -50.0,
"positive.elevation": 0.0,
"positive.id": null,
"positive.latitude": 0.0,
"positive.longitude": 0.0,
"positive.manufacturer": null,
"positive.type": null,
"positive.x": 50.0,
"sample_rate": 256.0,
"time_period.end": "2021-01-01T12:00:00+00:00",
"time_period.start": "2020-01-01T00:00:00+00:00",
"type": "electric",
"units": null
}
}
The values are updated in the experiment object.
[9]:
experiment.surveys[0].stations["mt01"].runs[0].channels["ex"]
[9]:
{
"electric": {
"channel_number": 0,
"component": "ex",
"data_quality.rating.value": 0,
"dipole_length": 100.0,
"filter.applied": [
false
],
"filter.name": [],
"measurement_azimuth": 10.0,
"measurement_tilt": 0.0,
"negative.elevation": 0.0,
"negative.id": null,
"negative.latitude": 0.0,
"negative.longitude": 0.0,
"negative.manufacturer": null,
"negative.type": null,
"negative.x": -50.0,
"positive.elevation": 0.0,
"positive.id": null,
"positive.latitude": 0.0,
"positive.longitude": 0.0,
"positive.manufacturer": null,
"positive.type": null,
"positive.x": 50.0,
"sample_rate": 256.0,
"time_period.end": "2021-01-01T12:00:00+00:00",
"time_period.start": "2020-01-01T00:00:00+00:00",
"type": "electric",
"units": null
}
}
From Field Notes
Field notes are important but can be a pain to keep track of, whether they are written in notebooks, kept on tablets, or in various formats. Say you have a spreadsheet of field notes and now you’d like to make some metadata objects.
[10]:
#TODO
[ ]: