ska_tdb¶
Access the Chandra Telemetry Database
The ska_tdb package provides a convenient mechanism to retrieve all data in
the Chandra ODB Telemetry Database (TDB) tables. The default values correspond
to the latest definitions available in the CSV (text) dump of the TDB. Versions
going back to P004 are also accessible (see TDB version).
A description of the tables is availble in the TDB table definitions section.
Usage¶
The TDB table entries can be accessed via the module-level variables tables
and msids. The msids variable is the main workhorse for ska_tdb, while
the tables variable is needed for tables that do not have an MSID column.
Msids¶
The msids variable allows access to all information related to a particular
MSID. It behaves like a Python dict where you use the MSID name
(case-insenstive) as the key. Once you have a particular MSID selected you can
then retrieve all table entries related to that MSID by accessing attributes
corresponding to the TDB table name.
Examples:
>>> from ska_tdb import msids
>>> msids.<TAB> # See available attributes
This returns the following, where all the TDB tables with MSID data begin with
capital “T” and columns from the tmsrment table are available as lower case
attributes:
msids.Tcntr msids.calibration_type msids.limit_switch_msid
msids.Tlmt msids.counter_msid msids.low_raw_count
msids.Tloc msids.data_type msids.msid
msids.Tmsrment msids.description msids.owner_id
msids.Tpc msids.ehs_header_flag msids.prop
msids.Tpp msids.eng_unit msids.range_msid
msids.Tsc msids.es_default_set_num msids.technical_name
msids.Tsmpl msids.es_switch_msid msids.total_length
msids.calibration_default_set_num msids.high_raw_count
msids.calibration_switch_msid msids.limit_default_set_num
If you examine any of those attributes for the msids variable you get the results for all MSIDS.
Now select a particular MSID and see that it has the same attributes:
>>> tephin = msids['tephin']
>>> tephin.<TAB> # See available attributes
tephin.Tcntr tephin.calibration_type tephin.limit_default_set_num
tephin.Tlmt tephin.counter_msid tephin.limit_switch_msid
tephin.Tloc tephin.data_type tephin.low_raw_count
tephin.Tmsrment tephin.description tephin.msid
tephin.Tpc tephin.ehs_header_flag tephin.owner_id
tephin.Tpp tephin.eng_unit tephin.prop
tephin.Tsc tephin.es_default_set_num tephin.range_msid
tephin.Tsmpl tephin.es_switch_msid tephin.technical_name
tephin.calibration_default_set_num tephin.find tephin.total_length
tephin.calibration_switch_msid tephin.high_raw_count
Finally look at the attributes:
>>> tephin.Tmsrment # MSID definition (description, tech name etc)
('TEPHIN', 'EPHIN SENSOR HOUSING TEMP', 'IUNS', 'PP', 'DEGF', 0, 255, 8,
'N', '0', '0', '0', 1, '0', 1, '0', 0, 'THM', 'LR/15/PA/2', 'U')
>>> tephin.Tpp # Calibration point pair values
array([('TEPHIN', 1, 15, 232, -51.90456), ('TEPHIN', 1, 9, 110, 47.0923),
('TEPHIN', 1, 14, 223, -38.30814),
('TEPHIN', 1, 13, 214, -27.81212),
('TEPHIN', 1, 12, 203, -17.23066), ('TEPHIN', 1, 11, 190, -6.5357),
('TEPHIN', 1, 10, 172, 6.45808), ('TEPHIN', 1, 16, 255, -103.49045),
('TEPHIN', 1, 1, 0, 215.03), ('TEPHIN', 1, 7, 76, 72.95052),
('TEPHIN', 1, 6, 64, 84.09784), ('TEPHIN', 1, 5, 54, 94.86368),
('TEPHIN', 1, 4, 46, 104.89), ('TEPHIN', 1, 3, 38, 116.7678),
('TEPHIN', 1, 2, 28, 135.846), ('TEPHIN', 1, 8, 91, 60.77076)],
dtype=[('MSID', '|S14'), ('CALIBRATION_SET_NUM', '<i8'), ('SEQUENCE_NUM', '<i8'),
('RAW_COUNT', '<i8'), ('ENG_UNIT_VALUE', '<f8')])
>>> tephin.Tsc # No state codes so it returns None
>>> tephin.technical_name
'EPHIN SENSOR HOUSING TEMP'
>>> tephin.data_type
'IUNS'
Finding MSIDs¶
With the msids object you can search the TDB for MSIDs of interest:
>>> msids.find('teph')
This applies the specified search expression to the MSID name, description, and technical description.
This returns a list of MsidView objects:
[<MsidView msid="TEPHIN" technical_name="EPHIN SENSOR HOUSING TEMP">,
<MsidView msid="TEPHTRP1" technical_name="HTR ENA/DIS: EIA/RCTU-EP/PSU1 PRI (CH0)">,
<MsidView msid="TEPHTRP2" technical_name="HTR ENA/DIS: EIA/RCTU-EP/PSU1 PRI (CH1)">,
<MsidView msid="TEPHTRR1" technical_name="HTR ENA/DIS: EIA/RCTU-EP/PSU1 RDNT (CH0)">,
<MsidView msid="TEPHTRR2" technical_name="HTR ENA/DIS: EIA/RCTU-EP/PSU1 RDNT (CH1)">]
The search value can be any valid Python regular expression, for instance pea1 followed
by at least one character followed by temperature::a
>>> msids.find('pea1.+temperature')
If required you can dig deeper, for instance:
>>> tephs = msids.find('teph')
>>> for x in tephs:
... print(x.msid, x.description, x.data_type)
('TEPHIN', 'LR/15/PA/2', 'IUNS')
('TEPHTRP1', 'EP/3/SD/0 ISATS MOM BEIA0W01 BIT 3 EIA/RCTU-EP PRI HTR ON/OFF (CH0)', 'IDIS')
('TEPHTRP2', 'EP/3/SD/1 ISATS MOM BEIA1W01 BIT 3 EIA/RCTU-EP PRI HTR ON/OFF (CH1)', 'IDIS')
('TEPHTRR1', 'EP/3/SD/0 ISATS MOM BEIA0W09 BIT 3 EIA/RCTU-EP RDNT HTR ON/OFF (CH0)', 'IDIS')
('TEPHTRR2', 'EP/3/SD/1 ISATS MOM BEIA1W09 BIT 3 EIA/RCTU-EP RDNT HTR ON/OFF (CH1)', 'IDIS')
Finally, you can provide multiple match arguments. This then returns the
logical-and result of running the find() call for each argument individually.
>>> msids.find('aca', 'filter')
[<MsidView msid="AOACIDPX" technical_name="ACA DATA PROCESSING DEFECTIVE PIXEL FILTER ENAB/DISA">,
<MsidView msid="AOACIIRS" technical_name="ACA DATA PROCESSING IONIZING RADIATION FILTER ENAB/DISA">,
<MsidView msid="AOACIMSS" technical_name="ACA DATA PROCESSING MULTIPLE STARS FILTER ENAB/DISA">,
<MsidView msid="AOACISPX" technical_name="ACA DATA PROCESSING SATURATED PIXEL FILTER ENAB/DISA">]
Tables¶
The tables variable allows direct access to TDB tables. This variable is a
special dict object that returns a TableView object when you ask for a TDB
table such as tmsrment (MSID descriptions) or tsc (MSID state codes).
After you import the tables variable you can ask for the names of all
available tables:
from ska_tdb import tables
tables.keys() # show all available tables
You then select a table with the table name (which must be lower case):
>>> tmsrment = tables['tmsrment']
With this table selected you can show the table, show all columns for that table, or get the values for a particular column:
>>> tmsrment # show the table
... <SNIP> ...
>>> tmsrment.colnames # column names for this table
('MSID', 'TECHNICAL_NAME', 'DATA_TYPE', 'CALIBRATION_TYPE', 'ENG_UNIT', 'LOW_RAW_COUNT',
'HIGH_RAW_COUNT', 'TOTAL_LENGTH', 'PROP', 'COUNTER_MSID', 'RANGE_MSID', 'CALIBRATION_SWITCH_MSID',
'CALIBRATION_DEFAULT_SET_NUM', 'LIMIT_SWITCH_MSID', 'LIMIT_DEFAULT_SET_NUM', 'ES_SWITCH_MSID',
'ES_DEFAULT_SET_NUM', 'OWNER_ID', 'DESCRIPTION', 'EHS_HEADER_FLAG')
>>> tmsrment['technical_name']
array(['OFFLINE SCIENCE DATA FOR ACIS 1 OF 2',
'OFFLINE SCIENCE DATA FOR ACIS ADDITIONAL', 'CAMERA BODY TEMP. A',
..., 'RCS-2 thruster valve 01 temperature (OBC reading)',
'RCS-2 thruster valve 02 temperature (OBC reading)',
'ACIS High Radiation Flag'],
dtype='|S59')
For tables that have an MSID column you can filter on the MSID to see only entries for that MSID. The MSID names are case-insensitive.
>>> tmsrment['tephin'] # only TEPHIN entries
('TEPHIN', 'EPHIN SENSOR HOUSING TEMP', 'IUNS', 'PP', 'DEGF', 0, 255, 8, 'N',
'0', '0', '0', 1, '0', 1, '0', 0, 'THM', 'LR/15/PA/2', 'U')
>>> tables['tsc']['aoattqt4'] # State codes for AOATTQT4
array([], dtype=[('MSID', '|S15'), ('CALIBRATION_SET_NUM', '<i8'), ('SEQUENCE_NUM', '<i8'),
('LOW_RAW_COUNT', '<i8'), ('HIGH_RAW_COUNT', '<i8'), ('STATE_CODE', '|S4')])
>>> tables['tpp']['TEPHIN'] # Point pair for TEPHIN
array([('TEPHIN', 1, 15, 232, -51.90456), ('TEPHIN', 1, 9, 110, 47.0923),
('TEPHIN', 1, 14, 223, -38.30814),
('TEPHIN', 1, 13, 214, -27.81212),
('TEPHIN', 1, 12, 203, -17.23066), ('TEPHIN', 1, 11, 190, -6.5357),
('TEPHIN', 1, 10, 172, 6.45808), ('TEPHIN', 1, 16, 255, -103.49045),
('TEPHIN', 1, 1, 0, 215.03), ('TEPHIN', 1, 7, 76, 72.95052),
('TEPHIN', 1, 6, 64, 84.09784), ('TEPHIN', 1, 5, 54, 94.86368),
('TEPHIN', 1, 4, 46, 104.89), ('TEPHIN', 1, 3, 38, 116.7678),
('TEPHIN', 1, 2, 28, 135.846), ('TEPHIN', 1, 8, 91, 60.77076)],
dtype=[('MSID', '|S14'), ('CALIBRATION_SET_NUM', '<i8'), ('SEQUENCE_NUM', '<i8'),
('RAW_COUNT', '<i8'), ('ENG_UNIT_VALUE', '<f8')])
TDB version¶
P010 is the default version of the TDB that is accessed. To change this, specify
the new version as an integer, e.g. 8 for version P008. In this example we
roll back time to P008 when the TEPHIN database limits were much lower:
>>> msids['tephin'].Tlmt
('TEPHIN', 1, 10.0, 150.0, 5.0, 999.0, 0, 5, 'A')
>>> import ska_tdb
>>> ska_tdb.set_tdb_version(8)
>>> msids['tephin'].Tlmt
('TEPHIN', 1, 10.0, 81.0, 5.0, 86.0, 0, 5, 'A')
API Documentation¶
TDB table definitions¶
tcntr¶
Column |
Type |
|---|---|
MSID |
string(8) |
STREAM_NUMBER |
int |
INIT_VALUE |
int |
END_VALUE |
int |
WRAP_AROUND_FLAG |
string(1) |
DIR |
string(1) |
DELTA |
int |
COUNTER_TYPE |
string(3) |
tes¶
Column |
Type |
|---|---|
MSID |
string(15) |
ES_SET_NUM |
int |
EXPECTED_STATE |
string(4) |
TOLER |
int |
EM_ALL_SAMP_FLAG |
string(1) |
tlmt¶
Column |
Type |
|---|---|
MSID |
string(14) |
LIMIT_SET_NUM |
int |
CAUTION_LOW |
float |
CAUTION_HIGH |
float |
WARNING_LOW |
float |
WARNING_HIGH |
float |
DELTA |
int |
TOLER |
int |
EM_ALL_SAMP_FLAG |
string(1) |
tloc¶
Column |
Type |
|---|---|
MSID |
string(15) |
STREAM_NUMBER |
int |
SYLLABLE_NUMBER |
int |
START_MINOR_FRAME |
int |
START_WORD |
int |
START_BIT |
int |
LENGTH |
int |
tmsrment¶
Column |
Type |
|---|---|
MSID |
string(15) |
TECHNICAL_NAME |
string(59) |
DATA_TYPE |
string(4) |
CALIBRATION_TYPE |
string(2) |
ENG_UNIT |
string(7) |
LOW_RAW_COUNT |
int |
HIGH_RAW_COUNT |
int |
TOTAL_LENGTH |
int |
PROP |
string(1) |
COUNTER_MSID |
string(8) |
RANGE_MSID |
string(8) |
CALIBRATION_SWITCH_MSID |
string(8) |
CALIBRATION_DEFAULT_SET_NUM |
int |
LIMIT_SWITCH_MSID |
string(8) |
LIMIT_DEFAULT_SET_NUM |
int |
ES_SWITCH_MSID |
string(7) |
ES_DEFAULT_SET_NUM |
int |
OWNER_ID |
string(4) |
DESCRIPTION |
string(240) |
EHS_HEADER_FLAG |
string(1) |
towner¶
Column |
Type |
|---|---|
OWNER_ID |
string(4) |
DESCRIPTION |
string(53) |
tpc¶
Column |
Type |
|---|---|
MSID |
string(9) |
CALIBRATION_SET_NUM |
int |
ENG_UNIT_LOW |
float |
ENG_UNIT_HIGH |
float |
DEG |
int |
COEF0 |
float |
COEF1 |
float |
COEF2 |
float |
COEF3 |
float |
COEF4 |
float |
COEF5 |
float |
COEF6 |
float |
COEF7 |
float |
COEF8 |
float |
COEF9 |
float |
tpp¶
Column |
Type |
|---|---|
MSID |
string(14) |
CALIBRATION_SET_NUM |
int |
SEQUENCE_NUM |
int |
RAW_COUNT |
int |
ENG_UNIT_VALUE |
float |
tsc¶
Column |
Type |
|---|---|
MSID |
string(15) |
CALIBRATION_SET_NUM |
int |
SEQUENCE_NUM |
int |
LOW_RAW_COUNT |
int |
HIGH_RAW_COUNT |
int |
STATE_CODE |
string(4) |
tsmpl¶
Column |
Type |
|---|---|
MSID |
string(15) |
STREAM_NUMBER |
int |
PAR_COMP |
string(2) |
SAMPLE_PER_GROUP |
int |
GROUP_SAMPLE_OFSET |
int |
SAMPLE_COMP |
string(1) |
SAMPLE_RATE |
int |
OFSET |
int |
START_COUNTER_VALUE |
int |
COUNTER_OFSET |
int |
LOW_RANGE |
int |
HIGH_RANGE |
int |
STATE_CODE |
string(4) |
CONTEXT_PACKET_ID |
int |
CONTEXT_LVT_LOCATION |
int |
tstream¶
Column |
Type |
|---|---|
STREAM_NUMBER |
int |
STREAM_TYPE |
string(1) |
STREAM_ID |
string(4) |
STREAM_FORMAT_ID |
string(3) |
PROTOCOL |
int |
STREAM_PRIORITY |
int |
STREAM_PROP |
string(1) |
STREAM_OWNER_ID |
string(4) |
STREAM_DESCRIPTION |
string(38) |
ttdm¶
Column |
Type |
|---|---|
TDM_ID |
string(4) |
FORMAT_ID_MSID |
string(8) |
TIME_MSID |
string(1) |
SYNC_PATTERN |
string(6) |
SYNC_PATTERN_MSID |
string(7) |
SYNC_LENGTH |
int |
ttdm_fmt¶
Column |
Type |
|---|---|
TDM_ID |
string(4) |
TDM_FORMAT_ID |
string(3) |
FORMAT |
int |
BITS_PER_WORD |
int |
WORDS_PER_MINOR_FRAME |
int |
MINOR_FRAMES_PER_MAJOR_FRAME |
int |
DATA_CYCLE |
int |
MAJOR_FRAME_PERIOD |
float |
ENCAP_STREAM_NUMBER |
int |
ENCAP_BOUNDARY |
string(1) |
ENCAP_FRAME_PER_PACKET |
int |