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fbinrecwrite

Writes a single unformatted sequential access Fortran record to a file.

Prototype

	procedure fbinrecwrite (
		path    [1] : string,   
		rec_num [1] : integer,  
		var         : numeric   
	)

Arguments

path

Pathname to binary file

rec_num

Record number to write to the file beginning at 0, -1 for append

var

A numeric variable of any dimensionality.

Description

fbinrecwrite writes a single unformatted sequential access binary record to the file path. If rec_num is equal to -1 then var is appended to the end of the file. If rec_num is not equal to -1 then it is the record number to be written.

By default, the elements of var are written to the file using the machine's native binary format. To force the byte order to be written as big-endian or little-endian, see the "WriteByteOrder" option in the setfileoption procedure.

By default, the record marker size at the beginning and end of Fortran sequential files is assumed to be 4 bytes. In V6.1.1 and later, you can change this to 8 bytes using the "RecordMarkerSize" option in the setfileoption procedure.

See Also

fbinnumrec, fbinrecread, fbindirread, fbinread, fbinwrite, fbindirwrite, setfileoption, isbigendian

Examples

Example 1

NCL code fragment: let a(5) be of type integer and x(100), y(399), z(64,128) be of type float. Append each succeeding record:

     filo = "example01"            ; output file    
     fbinrecwrite (filo, -1, a)     
     fbinrecwrite (filo, -1, x)
     fbinrecwrite (filo, -1, y) 
     fbinrecwrite (filo, -1, z)

Fortran (f77 here) code fragment: the read statements must be in the same order as they were in the fortran program:

     integer a(5)
     real    x(100), y(399), z(128,64)
     
     open (11,file="example01",form="unformatted", access="sequential")

     read (11) a
     read (11) x
     read (11) y
     read (11) z

Example 2:

NCL code fragment: assume that scalar variables year, mon, day and hour are to be written to a file, in addition to, say, three multi-dimensional grids, say, u(64,128), v(64,128), z(64,128,17,31):

     filo    = "example02"       ; output file    
     time    = new ( 4, "integer")
     time(0) = year              ; explicitly assign 
     time(1) = mon
     time(2) = day
     time(3) = hour
     fbinrecwrite (filo, -1, time) 
     fbinrecwrite (filo, -1, u ) 
     fbinrecwrite (filo, -1, v ) 
     fbinrecwrite (filo, -1, z ) 

Fortran code fragment to read:

     integer itime(4)
     real    u(128,64), v(128,64), z(64,128,17,31)
     
     open (11,file="example02",form="unformatted", access="sequential")

     read (11) itime
     read (11) u
     read (11) v
     read (11) z

Example 3: let data(ntim,nfld,nlvl,nlat,mlon) be of type double

Use NCL to write as one physical record:

     fbinrecwrite (filo, -1, data ) 

Fortran:

     double precision data(ntim,nfld,nlvl,nlat,mlon)
     open (unit=8, file=`data.ieee', form=`unformatted')
     read (8) data

Example 4: let data(ntim,nfld,nlvl,nlat,mlon) be of type float and, for some reason, it is desired to write two-dimensional records. Here, ntim=2, nfld=8, nlvl=18, nlat=73, mlon=144.

    do i=0,ntim-1
     do j=0,nfld-1
      do k=0,nlvl-1
         fbinrecwrite (filo, -1, data(:,:,k,j,i) ) 
       enddo
     enddo
    enddo

Fortran code fragment (one way to read the data):

    integer mlon, nlat, nlvl, nfld, ntim
    parameter (mlon=144)  ! number of longitudes 
    parameter (nlat=73)   ! number of latitudes 
    parameter (nlvl=18)   ! number of levels   
    parameter (nfld=8)    ! number of variables 
    parameter (ntim=2)    ! number of time steps  
    real data(mlon,nlat)

    open (unit=8, file=`data.ieee', form=`unformatted')
    do i=1,ntim
     do j=1,nfld
      do k=1,nlvl
         read (8) data    ! this will be 2D
       enddo
     enddo
    enddo

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