That's right by C language convention.  Your data are by FORTRAN
convention, for example.  If the general array importer you can specify
this by row vs. column majority.  In the DX format, try something like
origin 0 200
delta 0 -1
delta 1 0
or variations on this to force the reading of the array in the way you
want.

If the positions array is read correctly but the order is wrong, you can
use Transpose to switch the order (adds a pointer but doesn't copy or
reorder the data)

Once the vector field is imported you can use Compute to switch x and y (or
u and v) because of DX's handedness.


"Thomas A. Gardiner" <[EMAIL PROTECTED]>@opendx.watson.ibm.com on
06/20/2000 08:58:00 AM

Please respond to [email protected]

Sent by:  [EMAIL PROTECTED]


To:   [email protected]
cc:
Subject:  [opendx-users] right-handed vs left-handed



Hi,

I'll try to keep this short.  In DX the native file format says that the
"last index varies fastest".  I have a 2-D grid with x varying fastest and
z varying slowest.  So I define positions like so

object 1 class gridpositions counts 401 201
origin  0  0
delta   0  1
delta   1  0

This displays nicely and all, but DX thinks that the first index is x and
the second is y.  So my original grid which is (x,y,z) gets mapped to
(x,z,y).  Now for scalars, who cares, but for vectors and more importantly
pseudovectors like magnetic fields this is an important point; my
coordinate system has just changed from being right-handed to left-handed.

Would anyone happen to know a solution for this other than rewriting my
original data file to suit DX?

Thanks,
Tom

_________________________________________________________________________
Thomas Gardiner
[EMAIL PROTECTED]

University of Rochester
Department of Physics and Astronomy
P. O. Box 270171
Rochester, NY 14627-0171

(716) 275-9625 Office
(716) 275-8527 fax
__________________________________________________________________________

The scientist does not study nature because it is useful; he studies it
because he delights in it, and he delights in it because it is beautiful.
If nature were not beautiful, it would not be worth knowing, and if nature
were not worth knowing, life would not be worth living.- Henri Poincare
__________________________________________________________________________



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