ROMSslice modification

[simion1232006]

Matt,

I found the previous ROMSslice class was not very straightforward, so I modified it a little bit. Once you do this, everyone can make a slice time series with a function input rather than modified the tstep in object.
'object'= ROMSslice(filename,np.linspace(123.2,121.95,50),np.linspace(-15.5,-14.1,50))
temp_slice = 'object'('zeta',range(0,10)) ;

Note there is also a bug fix(could you please check whether this is right?)
data[tt,:,:] = self.F(dataslice[tt,:,:].ravel())
data[:,kk,:] = self.F(dataslice[kk,:,:].ravel())

Maybe you can merge this into your branch.
def call(self,varname,tstep=None):
# Load the data

numstep = len(self.time)

    dataslice = self.loadData(varname=varname,tstep=tstep)

    ndim = dataslice.ndim
    # Create the interpolation object
    self.xy = np.array([self.X.ravel(),self.Y.ravel()]).T

    self.F = interpXYZ(self.xy,self.xyout)

Nt = len(self.tstep)

    Nt = len(tstep)
    Nk = len(self.K)

    # Interpolate onto the output data
    data = np.zeros((Nt,Nk,self.nslice))

    if ndim == 2:
        return self.F(dataslice.ravel())
    elif Nt>1 and Nk==1 and ndim==3:
        for tt in range(Nt):

            data[tt,:,:] = self.F(dataslice[tt,:,:].ravel())
    elif Nk>1 and Nt==1 and ndim==3:
        for kk in range(Nk):

            data[:,kk,:] = self.F(dataslice[kk,:,:].ravel())           
    elif ndim == 4: # 4D array
        for kk in range(Nk):
            for tt in range(Nt):

                data[tt,kk,:] = self.F(dataslice[tt,kk,:,:].ravel())
    data[data>1e36]=0.
    return data.squeeze()