Vector dimesions are different before encoding json and after decoding json

Question

CHV 2022-3-3

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评论： CHV 2022-3-9

Before encoding to json file the mat files are having vectors are as row vector. But after encoding (jsonencode) and decoding(jsondecode), the vectors are changed to column vectors in workspace. And I want the same dimensions after decoding also, how can I get that ?

b.c = 22;

a= jsonencode(b);

d=jsondecode(a);

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KSSV 2022-3-3

You can transpose right?

CHV 2022-3-3

编辑：CHV 2022-3-3

Transpose is easy for few variables and above one I have shown is just one variable.But I am having lot of variables with different dimensions as structure array.After decoding I need same dimensions as before encoding.

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Answer 1

Ive J 2022-3-3

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编辑：Ive J 2022-3-3

在 MATLAB Online 中打开

How about this?

mystr.f1 = 1:4;
mystr.f2 = (1:4).';
js = jsonencode(mystr);
newstr = jsondecode(js)
newstr = struct with fields:
    f1: [4×1 double]
    f2: [4×1 double]
fnames = fieldnames(mystr);
fnames = fnames(structfun(@isrow, mystr)); % field names to be changed
for i = 1:numel(fnames)
    newstr.(fnames{i}) = newstr.(fnames{i}).';
end
newstr
newstr = struct with fields:
    f1: [1 2 3 4]
    f2: [4×1 double]

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Ive J 2022-3-3

在 MATLAB Online 中打开

jsondecode output will be always a column vector irrespective of your input structure. So, you have to find another way of passing dimensions of vectors stored in your initial structure (mystr in my example), because you cannot infer it from a decoded json anyway. You can also work with mps.json.encode which is the schema for MATLAB Production Server, and especially designed for MATLAB data types. Note the difference between column and row vectors in this case:

x.a = 1:3; x.b = (1:3)';
js = mps.json.encode(x)
js = '{"a":[[1,2,3]],"b":[1,2,3]}'
% decode again
newx = mps.json.decode(js)
newx = struct with fields:
    a: [1 2 3]
    b: [3×1 double]