VXi VT1422A 사용자 설명서

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VT1422A Command Reference   249
ALGorithm
Note
If <alg_name> specifies an undefined algorithm, ALG:TIME? returns 0. This can be 
used to determine whether algorithm <alg_name> is defined.
This command forces algorithms to run internally. If an algorithm contains a run-time 
error, no data can be returned and the command will not complete (will "hang").
When Accepted: Before INIT only.
Returned Value: numeric value. The type is float32
Send with VXIplug&play Function: hpe1422_cmdReal64_Q(...)
ALGorithm:FUNCtion:DEFine 
ALGorithm:FUNCtion:DEFine ’<function_name>’,<range>,<offset>, 
<func_data
defines a custom function that can be called from within a custom 
Parameters
Comments
By providing this custom function capability, the VT1422A's algorithm 
language can be kept simple in terms of mathematical capability. This increases 
speed. Rather than having to calculate high-order polynomial approximations 
of non-linear functions, this custom function scheme loads a pre-computed 
look-up table of values into memory. This method allows computing virtually 
any transcendental or non-linear function in only 17 µs. Resolution is 16 bits.
<function_name> is a global identifier and cannot be the same as a previously 
define global variable. A user function is globally available to all defined algorithms.
Values are generated for <range>, <offset>, and <func_data> with a program 
supplied with the VT1422A. It is provided in C-SCPI and BASIC forms. 
For full information, see Appendix F "Generating User Defined Functions" on 
page 487.
Parameter
Name
Parameter
Type
Range of
Values
Default 
Units
function_name
string
valid 'C' identifier
(if not already defined in 'GLOBALS')
none
range
numeric (float32)
see comments
none
offset
numeric (float32)
see comments
none
func_data
 512 element array of 
uint16
see comments
none