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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 or long,  
		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 values that describe how to shape the data, or -1 if the size of the record is unknown.

As of version 6.0.0, rec_dims can be of type int or long.

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 rec_dims. The data type of the record is specified by the parameter rec_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