FI H - File Information - Retrieve file Header values by name

PURPOSE

Retrieve particular values from a SPIDER or MRC file header by name and optionally place variable values in specified register variables.   Example.

SEE ALSO

FI	[File Information - List and retrieve file header value(s) by location]
ST H	[Set values in image/volume Header by name]
ST	[Set values in data file header]

USAGE

.OPERATION: FI H [cols],[ang]

[This operation takes a variable number of optional register variables. On completion of the operation, the variable(s) receive the values in header locations specified by their SPIDER header variable names.]

.INPUT FILE: PIC002
[SPIDER or MRC file name.]

If register variables are present on the operation line SPIDER asks:

.HEADER VARIABLE(S): NX, PHI
[Enter names of standard variables stored in header of SPIDER format images/volumes. Here: value of NX (SPIDER file header location: 12) (also called: NSAM) will be placed in register variable: [cols] and value of PHI (SPIDER file header location: 15) will be placed in register variable: [ang] ]

NOTES

1. If FMIN, FMAX, AV, or SIG values are requested and they are not yet available in header then they are calculated here. This is different behaviour from operation 'FI'.

2. SPIDER file header locations.

3. MRC file header locations.

SUBROUTINES

INQUIREHEAD, FILDAT, REG_SET, GETLAB

CALLER

UTIL1