[SciPy-user] bivariate spline

[Christian Kristukat]

Hi,
I was trying to use interpolate.bisplrep on a series of data points and I got 
the following error:

numerix Numeric 23.0
  iopt,kx,ky,m= 0 3 3 30
  nxest,nyest,nmax= 9 9 9
  lwrk1,lwrk2,kwrk= 1410 571 34
  xb,xe,yb,ye= -9.68459276E-07  14.1335814  2.7324011  22.748873
  eps,s  1.E-16  22.2540333
Traceback (most recent call last):
   File "relax_6.py", line 1001, in ?
     main()
   File "relax_6.py", line 976, in main
     bsp  = bisplrep(x,y,h)
   File "/usr/lib/python2.3/site-packages/scipy/interpolate/fitpack.py", line 
611, in bisplrep
     tx,ty,nxest,nyest,wrk,lwrk1,lwrk2)
SystemError: error return without exception set

x,y,h are all 1dim float arrays. I'm using a quite recent version of scipy from 
cvs and python 2.3 on linux.

I'm a little confused about the usage of the bisplrep function. What type of 
input is allowed? I successfully tried with the rank-2 arrays output of mgrid[,] 
but with rank-1 arrays describing some points I get the error above. Are there 
different fortran subroutines being called depending on the input and is my type 
of input valid or did I misunderstand something?

Regards, Christian