apstrim 2.0.1

Parameter and Object Serializer for EPICS, ADO or LITE

apstrim

Logger and extractor of Control System parameters (a.c.a EPICS PVs).

• Supported infrastructures: ADO, EPICS, LITE.
• Very fast random access retrieval of objects for selected time interval. Retrieval performance of 300 million of floats per second has been demonstrated.
• Nonhomogeneous and homogeneous data are processed equally fast.
• Scalar and vector data could be mixed.
• Data with different updating frequency can be mixed.
• Self-describing data format, no schema required.
• Efficient binary serialization format.
• Like JSON. But it's faster and smaller.
• Numpy arrays supported.
• Fast online compression.
• Basic plotting of the logged data.
• Data extraction from a file is allowed when the file is being written.

Installation

Dependencies: msgpack, caproto, lz4framed. These packages will be installed using pip:

pip3 install apstrim

The example program for deserialization and plotting apstrim.view, requires additional package: pyqtgraph.

API refrerence

apstrim

scan

Examples

Serialization

:python -m apstrim -nEPICS testAPD:scope1:MeanValue_RBV
pars: {'testAPD:scope1:MeanValue_RBV': ['0']}
21-06-19 11:06:57 Logged 61 paragraphs, 1.36 KBytes
...

:python -m apstrim -nEPICS --compress testAPD:scope1:MeanValue_RBV
pars: {'testAPD:scope1:MeanValue_RBV': ['0']}
21-06-19 11:10:35 Logged 61 paragraphs, 1.06 KBytes
...
# Compression ratio = 1.28

:python -m apstrim -nEPICS testAPD:scope1:MeanValue_RBV,Waveform_RBV
21-06-18 22:51:15 Logged 122 paragraphs, 492.837 KBytes
...

:python -m apstrim -nEPICS --compress testAPD:scope1:MeanValue_RBV,Waveform_RBV
21-06-19 11:04:58 Logged 122 paragraphs, 492.682 KBytes
...
# Note, Compression is poor for floating point arrays with high entropy.

python -m apstrim -nLITE liteHost:dev1:cycle
pars: {'acnlin23:dev1:cycle': ['0']}
21-06-19 11:16:42 Logged 5729 paragraphs, 103.14 KBytes
...

:python -m apstrim -nLITE --compress liteHost:dev1:cycle
21-06-19 11:18:02 Logged 5733 paragraphs, 53.75 KBytes
...
# Compression ratio = 1.9

Example of deserialization and plotting of all parameters from several logbooks.

python -m apstrim.view -i all -v -p *.aps