cdfextract             package:clim.pact             R Documentation

_E_x_t_r_a_c_t _a _s_u_b_f_i_e_l_d _f_r_o_m _a _n_e_t_C_D_F _f_i_l_e.

_D_e_s_c_r_i_p_t_i_o_n:

     A slow routine that extraxcts a subfield. This routine is suitable
     for reading subsections of large data files that are too big for
     `retrieve.nc'.

_U_s_a_g_e:

     cdfextract(filename,varname,x.rng=NULL,y.rng=NULL,t.rng=NULL,
                       greenwich=TRUE,x.nam="lon",y.nam="lat",t.nam="tim",
                            plot=FALSE,l.scale=TRUE)

_A_r_g_u_m_e_n_t_s:

filename: name of netCDF file.

 varname: name ov variable.

   x.rng: X-range (in degrees East): c(min,max).

   y.rng: Y-range (in degrees North): c(min,max).

   t.rng: T-range (in units stored in 'tim'): c(min,max).

greenwich: TRUE: longitude runs from -180E to 180E.

   x.nam: name of X-dimension.

   y.nam: name of Y-dimension.

   t.nam: name of T-dimension.

    plot: TRUE for plotting.

 l.scale: scale field by offset and scaling-factor.

_V_a_l_u_e:

     a field object. Also see `retrieve.nc'. Saves the extracted data
     in a netCDF file called "cdfextract.nc" under current working
     directory (see `r2cdf').

_A_u_t_h_o_r(_s):

     R.E. Benestad

_E_x_a_m_p_l_e_s:

     slp <- cdfextract("data/nmc_slp.nc","slp",x.rng=c(-80,40),y.rng=c(20,75),
                       t.rng=c(times[is],times[is]+499),plot=FALSE)

