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Procedure:
dmpa2dsl
Purpose: MMS coordinate transformation:
DMPA <--> DSL
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| This is currently a placeholder and only |
| performs an identity transformation! |
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Inputs
TBD
Keywords:
/dsl2dmpa: Inverse transformation
/IGNORE_DLIMITS: If the specified from coord is different from the
coord system labeled in the dlimits structure of the
tplot variable setting this keyword prevents an error.
Example:
Notes:
$LastChangedBy: aaflores $
$LastChangedDate: 2015-12-21 19:27:01 -0800 (Mon, 21 Dec 2015) $
$LastChangedRevision: 19640 $
$URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/tags/spedas_2_1/projects/mms/common/cotrans/dmpa2dsl.pro $
(See projects/mms/common/cotrans/dmpa2dsl.pro)
Procedure: dmpa2gse
Purpose: MMS coordinate transformation:
DMPA <--> GSE
interpolates, right ascension, declination
updates coord_sys attribute of output tplot variable.
inputs
name_mms_xxx_in ... data to transform (dmpa coordinates)
name_mms_spinras ... right ascension of the L-vector (J2000 coordinates)
name_mms_spindec ... declination of the L-vector (J2000 coordinates)
name_mms_xxx_out ... name for output (t-plot variable name)
keywords:
/GSE2DMPA inverse transformation
/IGNORE_DLIMITS if the specified from coord is different from the
coord system labeled in the dlimits structure of the tplot variable
setting this keyword prevents an error
Example:
Notes:
Based on dsl2gse from THEMIS, forked 6/22/2015
dmpa2gse is functionally equivalent to dsl2gse, and with proper
input it can be used to perform a DSL to GSE transformation,
as described below.
MEC L_vec assumes rigid-body rotation even when the wire booms
are oscillating, and thus, at any point in time it does not
give L, but rather the average orientation of the nutating
MPA (which is also assumed fixed relative to the rigid body)
as it wobbles in inertial space with a period of ~7 minutes.
When the user wants a DSL to GSE transformation, this can be done
if the spinra/spindec give the actual orientation of the angular
momentum vector. This can come from:
predatt (e.g. via AFG/DFG QL RADec_gse), or
defatt, (e.g. via MEC L_vec data), sufficiently smoothed to remove any ‘wobble’
- The wobble is large: it can be as large as 0.2 degrees in amplitude
right after a maneuver, and still as large as 0.1 degrees 12 hours
after a maneuver.
- A gaussian filter with a low-pass cutoff low enough to clobber the
7-minute wobble works well.
$LastChangedBy: egrimes $
$LastChangedDate: 2017-06-12 15:08:37 -0700 (Mon, 12 Jun 2017) $
$LastChangedRevision: 23455 $
$URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/tags/spedas_2_1/projects/mms/common/cotrans/dmpa2gse.pro $
(See projects/mms/common/cotrans/dmpa2gse.pro)
Procedure:
mms_cotrans
Purpose:
Transform between MMS and geophysical coordinate systems.
Calling Sequence:
mms_cotrans, input_name [,output_name]
,out_coord=out_coord [,out_suffix=out_suffix]
[,in_coord=in_coord] [,in_suffix=in_suffix] ...
Example Usage:
mms_cotrans, 'mms1_fgm_b_gse_srvy_l2_bvec', in_coord='dmpa', out_coord='gsm', $
out_suffix='_gsm', /ignore_dlimits
Arguments:
input_name: String or string array of input tplot variable(s). Standard tplot
wildcards may be used to specify multiple variables.
output_name (optional) String or string array of output tplot variable names.
Number of output names must match number of input names once
wildcards are considered.
Keywords:
in_coord: String specifying the coordinate system of the input(s).
This keyword is optional if the dlimits.data_att.coord_sys attribute
is present for the tplot variable, and if present, it must match
the value of that attribute (see cotrans_set_coord, cotrans_get_coord).
e.g. 'dmpa', 'gse', 'gsm', 'sm', 'gei','geo', 'mag'
out_coord: String specifying the desitnation coordinate system.
e.g. 'dmpa', 'gse', 'gsm', 'sm', 'gei','geo', 'mag'
in_suffix: Suffix of input variable name. This specifies the portion of
the input variable's name that will be replace with the output
suffix. If specified, the name effective input name will be
input_name + in_suffix
out_suffix: Suffix appended to the output name. If in_suffix is present or
the input coordinates are part of the input variable's name then
they will be replaced with out_suffix.
support_suffix: Suffix appended to standard support data names when looking
for support data (i.e. RA & Dec)
out_vars: return a list of the names of any transformed variables
valid_names: return valid coordinate system names in named variables supplied to
in_coord and/or out_coord keywords.
ignore_dlimits: set this keyword to true so that an error will not
be produced if the internal label of the coordinate system clashed
with the user provided coordinate system.
no_update_labels: Set this keyword if you want the routine to not update the labels automatically
Notes:
Based on thm_cotrans
$LastChangedBy: egrimes $
$LastChangedDate: 2017-06-12 15:08:37 -0700 (Mon, 12 Jun 2017) $
$LastChangedRevision: 23455 $
$URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/tags/spedas_2_1/projects/mms/common/cotrans/mms_cotrans.pro $
(See projects/mms/common/cotrans/mms_cotrans.pro)
Procedure: mms_cotrans_parse Purpose: Parse input coordinates stored in suffix string. This should allow coordinates systems denoted non-three-character strings and handle disambiguation between systems with identical substrings. Calling Sequence: coord_string = mms_cotrans_parse(input_string, valid_strings) Input: input_string: The suffix to be parsed (scalar) valid_strings: Array of valid coordinate strings Output: return value: Returns recognized coordinate or empty string if none found. Notes: $LastChangedBy: egrimes $ $LastChangedDate: 2016-05-25 15:38:52 -0700 (Wed, 25 May 2016) $ $LastChangedRevision: 21208 $ $URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/tags/spedas_2_1/projects/mms/common/cotrans/mms_cotrans_parse.pro $
(See projects/mms/common/cotrans/mms_cotrans_parse.pro)
Procedure: mms_cotrans_qrotate Purpose: Perform a quaternion rotation on a tplot variable Calling Sequence: mms_cotrans_qrotate, name_in, quaternion_name [,name_out] [,inverse=inverse] Input: name_in: Tplot variable to be transformed quaternion_name: Tplot variable containing MMS rotation quaternion name_out: New name for output variable, if not specified the original is overwritten inverse: Flag to apply inverse rotation out_coord: String specifying output coordinates for updating dlimits Output: none, may alter or create new tplot variable Notes: $LastChangedBy: aaflores $ $LastChangedDate: 2016-05-25 18:22:33 -0700 (Wed, 25 May 2016) $ $LastChangedRevision: 21214 $ $URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/tags/spedas_2_1/projects/mms/common/cotrans/mms_cotrans_qrotate.pro $
(See projects/mms/common/cotrans/mms_cotrans_qrotate.pro)
Procedure: mms_cotrans_qtransformer Purpose: Helps simplify transformation logic code using a recursive formulation. Rather than specifying the set of transformations for each combination of in_coord & out_coord, this routine will perform only the nearest transformation then make a recursive call to itself, with each call performing one additional step in the chain. This makes it so only neighboring coordinate transforms need be specified. All possible transformations currently go through ECI coordinates Input: in_name: name of variable to be transformed out_name: output name for transformed variable in_coord: coordinate system of the input out_coord: coordinate system of the output probe: probe designation for input variable Output: No explicit output, calls transformation routines and itself Notes: Modeled after thm_cotrans_transform_helper $LastChangedBy: aaflores $ $LastChangedDate: 2016-05-25 18:22:33 -0700 (Wed, 25 May 2016) $ $LastChangedRevision: 21214 $ $URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/tags/spedas_2_1/projects/mms/common/cotrans/mms_cotrans_qtransformer.pro $
(See projects/mms/common/cotrans/mms_cotrans_qtransformer.pro)
Procedure:
mms_cotrans_transformer
Purpose:
Helps simplify transformation logic code using a recursive formulation.
Rather than specifying the set of transformations for each combination of
in_coord & out_coord, this routine will perform only the nearest transformation
then make a recursive call to itself, with each call performing one additional
step in the chain. This makes it so only neighboring coordinate transforms
need be specified.
The set of possible transformations forms the following graph:
GSE<->AGSM
|
DMPA<->GSE<->GSM<->SM
|
GSE<->GEI<->GEO<->MAG
|
GEI<->J2000
Input:
in_name: name of variable to be transformed
out_name: output name for transformed variable
in_coord: coordinate system of the input
out_coord: coordinate system of the output
spinras: name of spacecraft right ascension variable
spindec: name of spacecraft declination variable
ingnore_dlimits: ignore variable metadata
Output:
No explicit output, calls transformation routines and itself
Notes:
- Modeled after thm_cotrans_transform_helper
- the dmpa2dsl transformation is an identity
transformation (dmpa is approximately the same as dsl;
see the notes in the header of dmpa2gse for more info)
$LastChangedBy: egrimes $
$LastChangedDate: 2017-06-12 15:08:37 -0700 (Mon, 12 Jun 2017) $
$LastChangedRevision: 23455 $
$URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/tags/spedas_2_1/projects/mms/common/cotrans/mms_cotrans_transformer.pro $
(See projects/mms/common/cotrans/mms_cotrans_transformer.pro)
Procedure:
mms_qcotrans
Purpose:
Perform coordinate transformations using MMS MEC quaternions.
This routine mirrors mms_cotrans but applies a different transformation.
Calling Sequence:
mms_qcotrans, input_name [,output_name]
,out_coord=out_coord [,out_suffix=out_suffix]
[,in_coord=in_coord] [,in_suffix=in_suffix] ...
Example Usage:
mms_qcotrans, 'mms1_fgm_b_gse_srvy_l2_bvec', in_coord='gse', out_coord='gsm', $
out_suffix='_gsm'
Arguments:
input_name: String or string array of input tplot variable(s). Standard tplot
wildcards may be used to specify multiple variables.
output_name (optional) String or string array of output tplot variable names.
Number of output names must match number of input names once
wildcards are considered.
Keywords:
in_coord: String specifying the coordinate system of the input(s).
This keyword is optional if the dlimits.data_att.coord_sys attribute
is present for the tplot variable, and if present, it must match
the value of that attribute (see cotrans_set_coord, cotrans_get_coord).
e.g. 'bcs','gse','gse2000','gsm','sm','geo','eci'
out_coord: String specifying the output coordinate system.
e.g. 'bcs','gse','gse2000','gsm','sm','geo','eci'
in_suffix: Suffix of input variable name. This specifies the portion of
the input variable's name that will be replace with the output
suffix. If specified, the name effective input name will be
input_name + in_suffix
out_suffix: Suffix appended to the output name. If in_suffix is present or
the input coordinates are part of the input variable's name then
they will be replaced with out_suffix.
out_vars: return a list of the names of any transformed variables
valid_names: return valid coordinate system names
no_update_labels: Set this keyword if you want the routine to not update the labels automatically
Notes:
This is a near clone of mms_cotrans and maybe be temporary
$LastChangedBy: egrimes $
$LastChangedDate: 2016-09-02 10:58:42 -0700 (Fri, 02 Sep 2016) $
$LastChangedRevision: 21791 $
$URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/tags/spedas_2_1/projects/mms/common/cotrans/mms_qcotrans.pro $
(See projects/mms/common/cotrans/mms_qcotrans.pro)
Procedure:
mms_qcotrans_check_rate
Purpose:
Verify that quaternion transformations have sufficient time
resolution for spinning/despinning data.
Calling Sequence:
bool = mms_qcotrans_check_times(in_coord, out_coord, probe)
Input:
in_coord: input coordinates string
out_coord: output coordinates
probe: probe designation
Output:
return value:
1 if required quaternion are present and have insufficient resolution
0 otherwise
Notes:
-Assumes all tranformations performed through ECI
$LastChangedBy: egrimes $
$LastChangedDate: 2016-05-25 15:38:52 -0700 (Wed, 25 May 2016) $
$LastChangedRevision: 21208 $
$URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/tags/spedas_2_1/projects/mms/common/cotrans/mms_qcotrans_check_rate.pro $
(See projects/mms/common/cotrans/mms_qcotrans_check_rate.pro)