When using the MATLAB jsonencode function it seems very difficult to convert size 1 arrays into the correct JSON format i.e. [value]. For example if I do:
jsonencode(struct('words', [string('hello'), string('bye')]))
Then this produces:
{"words":["hello","bye"]}
which is correct. If however I do:
jsonencode(struct('words', [string('hello')]))
Then it produces:
{"words":"hello"}
losing the square brackets, which it needs because it is in general an array. The same happens when using a cell rather than an array, although using a cell does work if it's not inside a struct.
Any idea how I can work around this issue?
It seems this can be solved by using a cell rather than an array and then not creating the struct inline. Like
s.words = {'hello'};
jsonencode(s)
Output:
{"words":["hello"]}
I presume when created inline the cell functionality of matlab is actually trying to make multiple structs rather than multiple strings. Note that this still won't work with arrays as matlab treats a size one array as a scalar.
Related
I'm looking for an elegant way of useing ndgrid and interpn in a more "general" way - basically for any given size of input and not treat each rank in a separate case.
Given an N-D source data with matching N-D mesh given in a cell-array of 1D vectors for each coordinate Mesh={[x1]; [x2]; ...; [xn]} and the query/output coordinates given in the same way (QueryMesh), how do I generate the ndgrid matrices and use them in the interpn without setting a case for each dimension?
Also, if there is a better way the define the mesh - I am more than willing to change.
Here's a pretty obvious, conceptual (and NOT WORKING) schematic of what I want to get, if it wasn't clear
Mesh={linspace(0,1,10); linspace(0,4,20); ... linsapce(0,10,15)};
QueryMesh={linspace(0,1,20); linspace(0,4,40); ... linsapce(0,10,30)};
Data=... (whatever)
NewData=InterpolateGeneric(Mesh,QueryMesh,Data);
function NewData=InterpolateGeneric(Mesh,QueryMesh,Data)
InGrid=ndgrid(Mesh{:});
OutGrid=ndgrid(QueryMesh{:});
NewData=interpn(InGrid{:},Data,OutGrid{:},'linear',0.0)
end
I think what you are looking for is how to get multiple outputs from this line:
OutGrid = ndgrid(QueryMesh{:});
Since ndgrid produces as many output arrays as input arrays it receives, you can create an empty cell array in this way:
OutGrid = cell(size(QueryMesh));
Next, prove each of the elements of OutGrid as an output argument:
[OutGrid{:}] = ndgrid(QueryMesh{:});
I want to work with a dynamic array using visual basic and I want that each element of the array will be an individual dynamic array too. How I should proceed? Thanks.
Read this - https://msdn.microsoft.com/en-us/library/aa716275(v=vs.60).aspx
And also this, in case you decide that reDim-ing things is annoying: https://msdn.microsoft.com/en-us/library/system.collections.arraylist(v=vs.110).aspx
Essentially though, you want to make an array and fill it with arrays. Then just treat those arrays independently for re-sizing purposes.
I have a cell array thiscells:
thiscells <1*40 cell>
eacharray of thiscells is 280*3
I have a function (TheFunction) that gets input of cell array that each array is X*2
How can I send a cell array to TheFunction that contain only columns1,3 from each array?
I tried
TheFunction(thiscells{:}(:,1:2)) % tring to send only columns 1,2
But it didn't work
Edit:
working with (but still looking for faster way to do so):
What is did so far
TheFunction(makingNewCells(thiscells,2));
when
makingNewCells:
[newCells]=makingNewCells(oldCells)
for ii=1:max(size(oldcells))
newCells=oldCells(:,[1 column]);
end
This question and its answers may be of help - thiscells{:}(:,1:2) is already failing without the call to Thefunction, if I am not mistaken.
For cells, the problem is even worse: add to this impossibility to double-subref that even if it did what you intended it to do, this passes 40 arguments (which are all 280x2 vectors) to Thefunction. I doubt there are (m)any legitimate uses for a function that takes 40 arguments of the same type, instead of having those wrapped in a cell. I would probably try doc cellfun first.
EDIT: just to be clear, I suggest changing Thefunction so that it accepts a cell of 40 matrices of size 280x2), then using
cell_of_twocolumned_arrays = cellfun(#(x)x(:,[1 2]),thiscells)
Alright let me explain detailed my question
this below image is displaying my matrix where i want to copy my data
Alright now what i want to do that is as you can see 1x4 cell
i want to copy it as an array to another variable such as
input_values=ones(1,4);%init
input_values=input_matrix_training(1);
So at the above i am trying to copy the elements in that cell array which is row 1 to the input_values array. But if i do as i above i am getting this instead of the values that array contains. ty
instead of above it should be like
The other values are a cell, and are thus best referenced with {} instead of (). Also, sometimes they need to be wrapped into [], depending on the format. Plus the fact that you don't need to initialize input_values, and what you should do becomes this:
input_values=[input_matrix_training{1}];
Or you can just use cell2mat
input_values=cell2mat(input_values(1));
Is it possible to create a multidimensional array of gtkwidgets? Specifically something like this:
mywidgetlist[2]["title"];
Or should I be doing this in a different way? How would I do this?
Basically I have a number of "widgets" (Loaded from gtkbuilder) composed of smaller widgets and I want to be able to change certain values, so this array setup seems preferable.
Is there another way of doing this (Other than actually coding a complete widget using signals etc and placing them in a simple array?)
In C, you cannot use a string to index into an array. Or, strictly speaking you can, but it's almost never what you want to do.
For C solution using glib (handy if you already use GTK+), consider a single-dimensional array of GHashTable pointers.