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craybinrecread

Reads COS blocked unformatted sequential access Fortran binary files.

Prototype

	function craybinrecread (
		path     [1] : string,   
		rec_num  [1] : integer,  
		rec_dims [*] : integer,  
		rec_type [1] : string    
	)

	return_val [rec_dims] :  rec_type

Arguments

path

Full or relative pathname to Cray COS blocked binary file.

rec_num

Record number to read from the file beginning at 0.

rec_dims

A singly dimensioned array of integer values that describe how to shape the data, or -1 if the size of the record is unknown.

rec_type

String name of the data type of the record.

Return value

As specified by the rec_dims, rec_type arguments.

Description

craybinrecread reads the rec_num record of the file path and shapes it according to the dimension sizes in parameter dims. The data type of the record is specified by the parameter type. If the size and dimensionality of the record are unknown the value -1 can be used for parameter rec_dims. In this case craybinrecread will read in the entire record as a singly dimensioned array. The file must be COS blocked.

See Also

craybinnumrec, fbinnumrec, fbinrecread fbinrecwrite

Examples

Example 1

The below is a Fortran (f77) code fragment that was run on a Cray: 

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

     write (11) a             ! 1st record   [rec_num=0]
     write (11) x             ! 2nd record   [rec_num=1]
     write (11) y             ! 3rd record   [rec_num=2]
     write (11) z             ! 4th record   [rec_num=3]

Below is the NCL code to read the above. Note that the shape appears to be different for the z variable. In Fortran, the leftmost dimension varies fastest while in NCL [C], the rightmost dimension varies fastest. Thus, the data record will match the fastest varying dimensions correctly. 

     fili = "example01"       ; input file    
     a = craybinrecread (fili, 0,   5, "integer")        ; 1st record is zero
     x = craybinrecread (fili, 1, 100, "float")          ; 2nd           one 
     y = craybinrecread (fili, 2, 399, "float")          ; 3rd record is two
     z = craybinrecread (fili, 3, (/ 64,128 /), "float") ; 4th record is three

; sample of reading *all* the float variable in one record.
; data will be a 1D array of length (100+399+128*64)
                                           
  data = craybinrecread (fili, 1, -1, "float")           ; read x, y, z as 1D