about: cubic root; load/save; struct member

[John W. Eaton]

On  8-Feb-2000, address@hidden <address@hidden> wrote:

| (-1)^(1./3.) yields
| 0.5 + i 0.86603
| is this the wanted behaviour?

Yes.  There are three roots: 0.5 + 0.86603i, -1, and 0.5 - 0.86603i.
Octave is returning the principal root.  (Funny that no one ever
complains that 1^(1/2) doesn't return -1.  :-)

| the file parameter of load and save could not be a variable containing
| a string ( the file name), is it possible to do something like
| filename = "a.dat"
| save -ascii filename
| (actually this yields an error)

Try

  filename = "a.dat";
  save ("-ascii", filename);

| is it possible to eliminate the member of a struct, so that the struct
| no longer contains it ?

Sorry, there is no function for this in the 2.0.x releases of Octave.
You could do it using a brute-force method, in which you copied all
the elements that you wanted to keep.

jwe



-----------------------------------------------------------------------
Octave is freely available under the terms of the GNU GPL.

Octave's home on the web:  http://www.che.wisc.edu/octave/octave.html
How to fund new projects:  http://www.che.wisc.edu/octave/funding.html
Subscription information:  http://www.che.wisc.edu/octave/archive.html
-----------------------------------------------------------------------