3.5.1 Creating and Reading SAV Files

To create a SAV file, use the program IUESAVE:

IUESAVE,'NAME',H,W,F,Q,flag 

NAME	IUESAVE will name the output file in the following way: It takes the name of the camera (e.g., LWP) and the image sequence number, and the string you enter as NAME, and concatenates them, with a .SAV extension. Example: Your data is for LWP 33333. Typing iuesave,'mgii',h,w,f,e would create file LWP33333MGII.SAV in the current directory.
H	Scale factor record, e.g., from IUESPEC.
W	Wavelengths.
F	Fluxes.
Q	Quality flags.
flag	If you don't want the file name to include the camera and image sequence number, you may enter 1. Then, the filename will be equal to your NAME parameter + .sav (e.g., RRLYR.SAV).

IUESAVE writes a file of the following format: the first four entries are the number of points in each of the four vectors H, W, F, Q. Then, those four vectors are written out sequentially (unformatted). IUESAVE checks to make sure your H vector isn't a string vector (e.g. a FITS header. If flag is not included or is equal to 0, it uses information in H to construct the file name.

To read the .SAV file you created, you can run IUEFETCH:

IUEFETCH,'FILENAME',H,W,F,Q 

The FILENAME parameter should be equal to the full file name of the file to be read ('LWP33333MGII' or 'RRLYR' in the examples used above).

IUESAVE writes H as an integer vector, and W, F, and Q as floating point vectors; they are converted as necessary when written. IUEFETCH reads them the same way. This means your Q vector (the quality flags) will be floating point.

For examples of IUESAVE, IUEFETCH, and SAVASC , see Table 3.4.

 

 

Table 3.4: SAV File Examples

Expression	Definition
iuesave,'test',h,w,f,q	Creates SWP13589TEST.SAV for data from SWP 13589.
iuesave,'rrlyr',h,w,f,q,1	Creates a file called RRLYR.SAV.
iuefetch,'rrlyr',h,w,f,q	Fetches data from RRLYR.SAV.
iuefetch,'SWP13589SM',h,w,f,q	Fetches data from SWP13589SM.SAV.
savasc,'SWP13589SM'	Creates an ASCII version (SWP13589SM.TXT) of the file SWP13589SM.SAV.