1.
2. Introduction
DEADLINE: end of March
2.1. Objectives:
- GET: To retrieve subset of data elements
- GET_SIZE: To interrogate the size of subset of data elements,
2.2. Assumptions:
GET_SLICEtype methods are not in the scope of the task (they are alternative ways to retrieve parts of the data elements) – although may be useful to add (independently of the deliverable) if straightforward to implement.- Implementation in Python only, no plans for other languages
- In case of nested AoS, it is not allowed to specify set of indices for AoS ancestors
- IMPLEMENTATION IN NEW LL ONLY!!!!!
3.
4. USE CASES:
- During the partial GET, only the requested node is returned (and the structure below if the node is not a leaf), not the whole structure above: get (« magnetics.flux_loop(i).flux ») à flux(t) for index (i) of its parent
- If the user specifies a set of indices for the parent, then the GET returns a reshaped leaf with an additional dimension (corresponding to the one of its parent). Reshaping is done while keeping time as the last dimension, to keep consistent with the IMAS DD rule (even if the reshaped leaf is not anymore a legal DD entity) :
- get (« magnetics.flux_loop(i1:i2).flux ») à flux(i1:i2, t)
- get (« equilibrium.time_slice(t1:t2).profiles_1d.q ») à q(:, t1:t2)
- In case of nested AoS, it is not allowed to specify set of indices for AoS ancestors. Only given values of AoS ancestors indices are handled : path/to/field/with/ancestorAoS(x:y)/field/AoS(n :m) is not managed by partial GET
Type of Field | Indices | Query | Output | |
---|---|---|---|---|
primitive/structure | NO | path/to/field/with/ancestorAoS(x)/field | primitive_type[1] structure[1] | |
primitive/structure | YES | path/to/field/with/ancestorAoS(i1:i2)/field | primitive_type[n] structure[n] | n=i2 - i1 |
primitive/structure | YES | path/to/field/with/ancestorAoS(x:y)/field/AoS(n :m)/field | ERROR | it is not allowed to specify set of indices for AoS ancestors |
AoS | NO | path/to/field/with/ancestorAoS(x)/field/AoS(y) | AoS[1] | if AoS is not a leaf, its "sub-structure" is filled in |
AoS | YES | path/to/field/with/ancestorAoS(x)/field/AoS(i1:i2) | AoS[n] | n=i2 - i1 if AoS is not a leaf, its "sub-structure" is filled in |
AoS | YES | path/to/field/with/ancestorAoS(x:y)/field/AoS(n :m) | ERROR | it is not allowed to specify set of indices for AoS ancestors |
AoS | YES | path/to/field/with/ancestorAoS(x:y)/field/AoS(1) | ERROR????? |
4.1. Time issue in heterogeneous
mode:
Let's assume Aos is tuple {data, time}
- GET(/path/to/AoS/) - OK
- GET(/path/to/AoS/data)
- Homogeneous mode: OK
- Heterogeneous mode: ERROR
- GET(/path/to/AoS/time)
- Homogeneous mode: ids%time
- Heterogeneous mode: ERROR
Example:
- get (« magnetics.flux_loop(i1:i2).flux ») returns flux(i1:i2). This is an AoS with data(t) and time(t) below, which can be of different sizes for the various indices i1:i2
- get (« magnetics.flux_loop(i1:i2).flux.data ») returns data(i1:i2,t) in homogeneous case, and an error message otherwise.
- ids_get(<path_including_indices>)
- input parameters
- pulseCtx (OR shot, run, user, tokamak, version)
- IDS name
- occurence
- QUERY
- output parameters
- array of primitive types (if query points to field of primitive type)
- array of structures (if query points to field of AoS type or structure)
- input parameters
query
syntax- separators ( / . | ) - path within tree
- brackets () [] - array
- indices (fortran style)
- ":" all elements
- "x:y" (from x to y)
- ":y" from begin to y
- "x:" from x to the last
- only the last bracket can contain indices:
- YES: "path/to/field/with/ancestorAoS(1)/field/AoS(n:m)"
- NO: "path/to/field/with/ancestorAoS(x:y)/field/AoS(1)"
Requested changes:
- Low Level:
- read_data - sanity check of type only when requested
- HLI:
- method for creating AoS (method of classes representing AoS array) OR resize(1)
- method to obtain AoS ctx
- AoS classes - a special field indicating that class is AoS
Algorithm:
Input: path
( /a/b/c(1)/d/e(m:n)/f/g
)
1) Convert path
to array/list {'a','b','c(1)','d','e(m:n)','f','g'}
2) Call traverse(ctx = p-fCtx, path, node = ids)
path/to/field/with/ancestorAoS(1)/field/AoS(n:m) -> AoS(n:m)
ancestorAoS(x:y)/field(:) --> field(:,x:y)
5. Shape of returned arrays
/path/with/AoS(i1:i2)/data
lets assume:
+ i1=1; i2=3 => number of AoS to be found ("range") is 2
+ len (data) == 5,
+ data for AoS(i1) = {11, 12, 13, 14, 15}
+ data for AoS(i2) = {21, 22, 23, 24, 25}
5.1. Non timed AoS
get (« magnetics.flux_loop(i1:i2).flux ») à flux(i1:i2, t)
If AoS is NON TIMED (AoS1 or AoS2) return array has shape (range, data_len)
In NumPy notation:
[[11, 12, 13, 14, 15]
[21, 22, 23, 24, 25]]
e.g.
arr(0,1) = 12
arr(1,2) = 23
5.2. Timed AoS
get (« equilibrium.time_slice(t1:t2).profiles_1d.q ») à q(:, t1:t2)
If AoS is TIMED (AoS3) return array has shape (data_len, range)
In NumPy notation:
[ [11,21]
[12,22]
[13,23]
[14,24]
[15,25] ]
e.g.
arr(0,1) = 21
arr(2,1) = 23
OPEN POINTS:
- AoS as ancestor(s) of queried data
- once implemented mechanism for creation of AoS could be reused to "go through" ancestors
- returned value
- type provided by user?
- AoS? if not - functionality can be placed at the Low Level and available for all HLIs (however it could be a problem with returned type anyway)
- Level of nesting
- path/AoS(indices)/x/y/z ?