Although this question was kind of already asked, it was closed because not enough information was given. Here is my attempt. I am trying to find out the correct format to import a vector data set (this will be an output from c and obviously I can put it in any format I want). The problem is a list vector data set from Mathematica is in a very interesting format, i.e.
data = Table[{-1 - x^2 + y, 1 + x - y^2}, {x, -3, 3, 1}, {y, -3, 3, 1}]
will give something that looks like,
{{{-13,-11},....},{{-8,-10}...}}
In trying to work backwards, I tried exporting the above table as
Export["test_vector.txt", data, "csv"]
then import it again as
a = Import["test_vector.txt", "csv"]
In looking at "a" compared to "data" it looks exactly the same except for a space between the vector components, i.e.
{{{-13, -11},....},{{-8, -10}...}}
I am able to
ListStreamPlot[data]
but when I go to do the same for "a" I get multiple errors, (Prat 1 of {} does not exist, Recursion depth of 1024 exceeded) and the statement that it is not a valid vector field dataset. (ListVectorPlot/ListStreamPlot; whichever, they both require the same type of dataset.)
Once again my question is, in what format do I need to put my data, so that I can import it into Mathematica as a vector dataset.