aeqdsk

Note

This documentation is incomplete. If you have information that could be added, please get in touch or a raise a pull request!

Warning

Sources do not agree on which values are stored in an A-EQDSK file, and in which order they are written. This implementation is based on A-EQDSK readers from FreeGS and eq_tools, but may not be appropriate for all A-EQDSK files.

If you have information that could help us alleviate this issue, please get in touch. A primary source recording which fields are included would be extremely helpful.

A-EQDSK files contain a wide variety of diagnostic data. It begins with a specially formatted header over the first 4 lines which contains:

• header: First row of the file

• shot: int, The shot number

• time: int, The time in milliseconds

• jflag: int, 0 if error

• iflag: int, >0 if error

• limloc: str, IN/OUT/TOP/BOT: limiter inside/outside/top/bot SNT/SNB: single null top/bottom DN: double null.

• mco2v: int, number of vertical CO2 laser chords. Should match length of arrays rco2v and dco2v.

• mco2r: int, number of radial CO2 laser chords. Should match length of arrays rco2r and dco2r.

• qmflag, str: axial q(0) flag, FIX if constrained and CLC for float

This is followed by a collection of variables expressed as floats, written 4 per line with a space at the beginning following the Fortran format (e17.9,3e16.9):

Initial block

Name	Default Value	Description
tsaisq	0.0	total chi2 from magnetic probes, flux loops, Rogowski and external coils
rcencm	100.0	major radius in cm for vacuum field BCENTR
bcentr	1.0	vacuum toroidal magnetic field in Tesla at RCENCM
pasmat	1000000.0	measured plasma toroidal current in Ampere
cpasma	1000000.0	fitted plasma toroidal current in Ampere-turn
rout	100.0	major radius of geometric center in cm
zout	0.0	Z of geometric center in cm
aout	50.0	plasma minor radius in cm
eout	1.0	Plasma boundary elongation
doutu	1.0	upper triangularity
doutl	1.0	lower triangularity
vout	1000.0	plasma volume in cm3
rcurrt	100.0	major radius in cm of current centroid
zcurrt	0.0	Z in cm at current centroid
qsta	5.0	equivalent safety factor q*
betat	1.0	toroidal beta in %
betap	1.0	poloidal beta with normalization average poloidal magnetic BPOLAV defined through Ampere’s law
ali	0.0	li with normalization average poloidal magnetic defined through Ampere’s law
oleft	10.0	plasma inner gap in cm
oright	10.0	plasma outer gap in cm
otop	10.0	plasma top gap in cm
obott	10.0	plasma bottom gap in cm
qpsib	5.0	q at 95% of poloidal flux
vertn	1.0	vacuum field (index? seems to be float) at current centroid

The next data block describes data related to CO2 lasers in the form of 4 1D arrays. These are similarly expressed 4-floats-per-line, with blank spaces on the last line if the array length is not a multiple of 4:

CO2 lasers

Name	Default Value	Description
rco2v	mco2v * [0.0]	1D array : path length in cm of vertical CO2 density chord
dco2v	mco2v * [0.0]	line average electron density in cm3 from vertical CO2 chord
rco2r	mco2r * [0.0]	path length in cm of radial CO2 density chord
dco2r	mco2r * [0.0]	line average electron density in cm3 from radial CO2 chord

This is followed by another general data block:

Second general block

Name	Default Value	Description
shearb	0.0
bpolav	1.0	average poloidal magnetic field in Tesla defined through Ampere’s law
s1	0.0	Shafranov boundary line integrals
s2	0.0	Shafranov boundary line integrals
s3	0.0	Shafranov boundary line integrals
qout	0.0	q at plasma boundary
olefs	0.0
orighs	0.0	outer gap of external second separatrix in cm
otops	0.0	top gap of external second separatrix in cm
sibdry	1.0
areao	100.0	cross sectional area in cm2
wplasm	0.0
terror	0.0	equilibrium convergence error
elongm	0.0	elongation at magnetic axis
qqmagx	0.0	axial safety factor q(0)
cdflux	0.0	computed diamagnetic flux in Volt-sec
alpha	0.0	Shafranov boundary line integral parameter
rttt	0.0	Shafranov boundary line integral parameter
psiref	1.0	reference poloidal flux in VS/rad
xndnt	0.0	vertical stability parameter, vacuum field index normalized to critical index value
rseps1	1.0	major radius of x point in cm
zseps1	-1.0
rseps2	1.0	major radius of x point in cm
zseps2	1.0
sepexp	0.0	separatrix radial expansion in cm
obots	0.0	bottom gap of external second separatrix in cm
btaxp	1.0	toroidal magnetic field at magnetic axis in Tesla
btaxv	1.0	vacuum toroidal magnetic field at magnetic axis in Tesla
aaq1	100.0	minor radius of q=1 surface in cm, 100 if not found
aaq2	100.0	minor radius of q=2 surface in cm, 100 if not found
aaq3	100.0	minor radius of q=3 surface in cm, 100 if not found
seplim	0.0	> 0 for minimum gap in cm in divertor configurations, < 0 absolute value for minimum distance to external separatrix in limiter configurations
rmagx	100.0	major radius in cm at magnetic axis
zmagx	0.0
simagx	0.0	Poloidal flux at the magnetic axis
taumhd	0.0	energy confinement time in ms
betapd	0.0	diamagnetic poloidal b
betatd	0.0	diamagnetic toroidal b in %
wplasmd	0.0	diamagnetic plasma stored energy in Joule
diamag	0.0	measured diamagnetic flux in Volt-sec
vloopt	0.0	measured loop voltage in volt
taudia	0.0	diamagnetic energy confinement time in ms
qmerci	0.0	Mercier stability criterion on axial q(0), q(0) > QMERCI for stability
tavem	0.0	average time in ms for magnetic and MSE data

The following parts of an A-EQDSK file are not present in old versions of the file. The next line describes the lengths of 4 further arrays using 4 ints in the Fortran format ‘(i6,3i5)’:

Extended section sizes

Name	Default Value	Description
nsilop	len(csilop)	Number of flux loop signals, len(csilop)
magpri	len(cmpr2)	Number of flux loop signals, len(cmpr2) (added to nsilop)
nfcoil	len(ccbrsp)	Number of calculated external coil currents, len(ccbrsp)
nesum	len(eccurt)	Number of measured E-coil currents

The next two arrays are stored in a concatenated fashion, so there is no newline between them if the length of the first array is not a multiple of four:

Extended arrays 1

Name	Default Value	Description
csilop	nsilop * [0.0]	computed flux loop signals in Weber
cmpr2	magpri * [0.0]

The following two arrays are stored similarly to the laser data:

Extended arrays 2

Name	Default Value	Description
ccbrsp	nfcoil * [0.0]	computed external coil currents in Ampere
eccurt	nesum * [0.0]	measured E-coil current in Ampere

The rest of the file consists of a further general data block. The total amount of variables depends on the exact A-EQDSK version:

Extended general block

Name	Default Value	Description
pbinj	0.0	neutral beam injection power in Watts
rvsin	0.0	major radius of vessel inner hit spot in cm
zvsin	0.0	Z of vessel inner hit spot in cm
rvsout	0.0	major radius of vessel outer hit spot in cm
zvsout	0.0	Z of vessel outer hit spot in cm
vsurfa	0.0	plasma surface loop voltage in volt, E EQDSK only
wpdot	0.0	time derivative of plasma stored energy in Watt, E EQDSK only
wbdot	0.0	time derivative of poloidal magnetic energy in Watt, E EQDSK only
slantu	0.0
slantl	0.0
zuperts	0.0
chipre	0.0	total chi2 pressure
cjor95	0.0
pp95	0.0	normalized P’(y) at 95% normalized poloidal flux
ssep	0.0
yyy2	0.0	Shafranov Y2 current moment
xnnc	0.0
cprof	0.0	current profile parametrization parameter
oring	0.0	not used
cjor0	0.0	normalized flux surface average current density at 99% of normalized poloidal flux
fexpan	0.0	flux expansion at x point
qqmin	0.0	minimum safety factor qmin
chigamt	0.0	total chi2 MSE
ssi01	0.0	magnetic shear at 1% of normalized poloidal flux
fexpvs	0.0	flux expansion at outer lower vessel hit spot
sepnose	0.0	radial distance in cm between x point and external field line at ZNOSE
ssi95	0.0	magnetic shear at 95% of normalized poloidal flux
rqqmin	0.0	normalized radius of qmin , square root of normalized volume
cjor99	0.0
cj1ave	0.0	normalized average current density in plasma outer 5% normalized poloidal flux region
rmidin	0.0	inner major radius in m at Z=0.0
rmidout	0.0	outer major radius in m at Z=0.0
psurfa	0.0	plasma boundary surface area, m^2
peak	0.0	peak to average plasma pressure
dminux	0.0	distance between limiter and upper x-point
dminlx	0.0	distance between limiter and lower x-point
dolubaf	0.0	distance from outer leg to upper baffle
dolubafm	0.0	distance at outboard midplane between last closed flux surface and the flux surface interesecting the upper baffle
diludom	0.0	distance from inner leg to upper dome
diludomm	0.0	distance at inner midplane between the last closed flux surface and the flux surface intersecting the upper dome
ratsol	0.0	ratio of flux expansion at inner midplane vs outer midplane
rvsiu	0.0	major radius of inner upper strikepoint
zvsiu	0.0	Z of inner upper strikepoint
rvsid	0.0	major radius of inner lower strikepoint
zvsid	0.0	Z of inner lower strikepoint
rvsou	0.0	major radius of outer upper strikepoint
zvsou	0.0	Z of outer upper strike point
rvsod	0.0	major radius of outer lower strike point
zvsod	0.0	Z of outer lower strike point
condno	0.0	condition number from least-squares fitting routine
dollbaf	0.0	distance from outer leg to lower baffle
dollbafm	0.0	distance from outer midplane last closed flux surface to the flux surface intersecting the lower baffle
dilldom	0.0	distance from inner leg to lower dome
dilldomm	0.0	distance from inner midplane last closed flux surface and the flux surface intersecting the lower dome
dummy_1	0.0	Purpose unknown
dummy_2	0.0	Purpose unknown

freeqdsk.aeqdsk.read(fh, data_fmt=None, extended_sizes_fmt=None)

Read an A-EQDSK file, returning a dictionary of data.

Parameters:

• fh (TextIO) – File handle to write to. Should be opened in a text read mode, i.e. open(filename, "r").

• data_fmt (Optional[str] (default: None)) – Fortran IO format for A-EQDSK data. If not provided, uses (e17.9,3e16.9).

• extended_sizes_fmt (Optional[str] (default: None)) – Fortran IO format for the line specifying array lengths in the extended portion of the A-EQDSK file. If not provided, uses (i6,3i5).

Return type:

Dict[str, Union[int, float, ndarray]]

freeqdsk.aeqdsk.write(data, fh, data_fmt=None, extended_sizes_fmt=None, time_fmt=None)

Write a dict of A-EQDSK data to a file.

Parameters:

• data (Dict[str, Union[float, int, _SupportsArray[dtype], _NestedSequence[_SupportsArray[dtype]], bool, complex, str, bytes, _NestedSequence[Union[bool, int, float, complex, str, bytes]]]]) – The A-EQDSK data to write to disk. It may also include header information.

• fh (TextIO) – File handle. Should be in a text write mode, i.e.``open(filename, “w”)``.

• data_fmt (Optional[str] (default: None)) – Fortran IO format for A-EQDSK data. If not provided, uses (e17.9,3e16.9).

• extended_sizes_fmt (Optional[str] (default: None)) – Fortran IO format for the line specifying array lengths in the extended portion of the A-EQDSK file. If not provided, uses (i6,3i5).

• time_fmt (Optional[str] (default: None)) – Fortran IO format for time stamps. If not provided, uses (e17.9).

Return type:

None

class freeqdsk.aeqdsk.Field(name, description='', default=None, has_length=None, length_of=None)

Helper dataclass for defining each entry in a A-EQDSK file.

default: Optional[float] = None

Default value to be assigned to missing fields when writing out an A-EQDSK dict. If set to None, the attributes has_length and length_of are used to determine a default

description: str = ''

Description of the field.

has_length: Optional[str] = None

If default is None and has_length is not None, the default value is determined by looking up the key assigned to has_length, and creating a list of 0.0 with that length. If this key does not exist, sets the value to [].

length_of: Optional[str] = None

If default is None and length_of is not None, the default value is determined by looking up the key assigned to length_of, and returning the length of the result. If this key does not exist, sets the value to 0.

name: str

Name of the field used in the resulting dict.

freeqdsk.aeqdsk.fields()

Returns full list of all Fields.

Return type:

Dict[str, Field]