wehub-resource-sync
33 lines
1.1 KiB
Markdown
33 lines
1.1 KiB
Markdown
---
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title: Time-align data
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order: 75
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---
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Real-world data is usually not time-aligned.
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Rerun provides capabilities to simplify time alignment.
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One common use case is to fill forward to run compute at a fixed frequency.
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This example demonstrates how Rerun simplifies that process.
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The dependencies in this example require `rerun-sdk[all]`, and `pandas` because python datetimes only support microsecond precision.
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## Setup
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Simplified setup to launch the local server for demonstration.
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In practice you'll connect to your cloud instance.
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snippet: howto/time_alignment[setup]
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## Extract desired timepoints
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Select start and end time of data, downsample to a fixed frequency, and specify those as the desired output timestamps.
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snippet: howto/time_alignment[extract_timepoints]
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## Time-align data
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Select the timeline, columns, and episode of interest.
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Extract rows at the specified time points, and fill forward to eliminate sparse entries.
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Finally, filter out nulls for initial sensor state that cannot be resolved with forward fill.
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snippet: howto/time_alignment[time_align]
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