Technical data

9-4
Understanding the CITIfile Data Format
The CITIfile Data Format
Keywords." When reading a CITIfile, unrecognized keywords should be ignored. This allows new keywords
to be added, without affecting an older program or instrument that might not use the new keywords. The
older instrument or program can still use the rest of the data in the CITIfile as it did before. Ignoring
unknown keywords allows backwards compatibility to be maintained.
CITIfile Examples
Example 2, An 8510 Display Memory File
Example 2 shows a simple file that contains no frequency information. Some instruments do not keep
frequency information for display memory data, so this information is not included in the CITIfile package.
Note that instrument-specific information (#NA= Network Analyzer information) is also stored in this file.
This convention allows the designer to define keywords that are particular to his or her particular
implementation.
Example:
CITIFILE A.01.00
#NA VERSION 8510B.05.00
NAME MEMORY
#NA REGISTER 1
VAR FREQ MAG 5
DATA S RI
BEGIN
-1.31189E-3,-1.47980E-3
-3.67867E-3,-0.67782E-3
-3.43990E-3,0.58746E-3
-2.70664E-4,-9.76175E-4
0.65892E-4,-9.61571E-4
END
Example 3, 8510 Data file
Example 3 shows a CITIfile package created from the data register of an 8510 Network Analyzer. In this
case 10 points of real and imaginary data was stored, and frequency information was recorded in a segment
list table.
Example:
CITIFILE A.01.00
#NA VERSION 8510B.05.00
NAME DATA
#NA REGISTER 1
VAR FREQ MAG 10
DATA S[1,1] RI
SEG_LIST_BEGIN
SEG 1000000000 4000000000 10
SEG_LIST_END
BEGIN
0.86303E-1,-8.98651E-1
8.97491E-1,3.06915E-1
-4.96887E-1,7.87323E-1
-5.65338E-1,-7.05291E-1
8.94287E-1,-4.25537E-1
1.77551E-1,8.96606E-1
-9.35028E-1,-1.10504E-1