SUB - Subtract images/volumes

PURPOSE

Subtracts one or more images or volumes from first input iamge. All inputs must have same dimensions. For legacy use this operation can be abbreviated to 'SU'   Example.

SEE ALSO

SUB 2	[Pairwise subtract series of real or complex images]
ADD	[Add images]
AR	[Arithmetic operation]

USAGE

.OPERATION: SUB

.INPUT FILE: PIC001
[Enter the name of the file from which the following files are to be subtracted. (Header positions from this file are transferred to output.)]

.SUBTRACTED FILE: PIC002
[Enter the name of the file to be subtracted from the first file. Can be same as the first input file.]

.OUTPUT FILE: PIC999
[Enter the name of the output file. Can be same as either input file.]

SPIDER will ask:

.SUBTRACTED FILE: PIC003
[Enter a '*' if no more subtractions are desired.]

[PIC002 is subtracted from PIC001, and the result is kept in PIC999. PIC003 is then subtracted from the new PIC001, and the result is again put into PIC999.]

NOTES

1. If multiple 'SUBTRACTED FILES' (e.g. PIC002, PIC003, PIC004...) are used the final output corresponds to serial subtraction: PIC999 = PIC001 - PIC002 - PIC003 - PIC004 ...

2. To subtract a series of images within a procedure you can use the following set of operations:

    
    [num] = 1 
    CP                ; Create constant value file 
      inp{***[num]}   ; First  file                 (input) 
      out999          ; File name                 (output) 
    DO  [num]=2,4     ; Creates running subtraction 
      SUB             ; Add files operation  
        out999        ; First  file               (input)  
        inp{***[num]} ; Second file               (input) 
        out999        ; Resulting file            (output) 
        *             ; Put asterick here  
    ENDDO 
   

SUBROUTINES

ADD

CALLER

UTIL2