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Simple metrics form the 'base' of the Metrics system. They are defined on a specific Type and reference timeseries data stored within.
Essentially, the Simple metric defines:

1. The Type on which the metric is defined
2. How to find the timeseries data on the Type
3. Configuration of the Normalization engine
4. The name of the metric

An example SimpleMetric is:

sample_met = c3.SimpleMetric.make({
	'id': 'SampleMetric_SampleType',
	'name': 'SampleMetric',
	'srcType': 'SampleType',
	'path': 'timeseriesValues',
	'expression': 'avg(avg(normalized.data.x))'
})

Please note that the above example does not have an example context in which it will work. This will be updated soon with a version backed up by a working exercise.

For more detail, see the C3 documentation on SimpleMetrics here: https://developer.c3.ai/docs/7.12.0/guide/guide-c3aisuite-basic/metrics-simple-metrics

CompoundMetrics

Compound metrics are generally easier to define and use as they operate on already defined metrics either Simple or Compound.
They essentially just consist of and id/name, and an expression defining the metric in terms of constants and already defined metrics.
If you try and execute a CompoundMetric on a type for which some necessary SimpleMetric is not defined, you'll get an error.

Essentially, a CompoundMetric defines:

1. The name/id of the metric
2. The expression defining the metric

An example CompoundMetric is:

sample_compound_met = c3.SimpleMetric.make({
	'id': 'CompoundMetric',
	'name': 'CompoundMetric',
	'expression': 'window("AVG", SimpleMetric, 0, 7)',
})

Please note that the above example does not have an example context in which it will work. This will be updated soon with a version backed up by a working exercise.

For more detail, see the C3 documentation on CompoundMetrics here: https://developer.c3.ai/docs/7.12.0/guide/guide-c3aisuite-basic/metrics-compound-metrics

Evaluating Metrics

Not all SimpleMetrics are defined on all types. Types on which you can evaluate a metric mixin the Type 'MetricEvaluatable' (C3 Docs here: https://developer.c3.ai/docs/7.12.0/type/MetricEvaluatable)
This bestows the function 'listMetrics' to that type, so if you're unsure what kind of metrics are available for a given type, execute that function to get a list, for example:

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