Keithley 707B, Справочное руководство

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Section 6: Instrument programming Models 707B and 708B Switching Matrix Reference Manual
6-30 707B-901-01 Rev. A / August 2010
Standard libraries
In addition to the standard programming constructs described in this document, Lua includes
standard libraries that contain useful functions for string manipulation, mathematics, and more. TSP
instruments also include instrument control extension libraries, which provide programming interfaces
to the instrumentation that can be accessed by the TSP. These libraries are automatically loaded
when the TSP starts and do not need to be managed by the programmer.
The following sections provide information on some of the basic Lua standard libraries. For additional
information, see the
NOTE
When referring to the Lua website, please be aware that TSP uses Lua 5.0.2.
Base library functions
Base library functions
Function Description
collectgarbage()
collectgarbage(limit)
Sets the garbage-collection threshold to the given limit (in Kbytes)
and checks it against the byte counter. If the new threshold is
smaller than the byte counter, then Lua immediately runs the
garbage collector. If there is no limit parameter, it defaults to 0
(which forces a garbage-collection cycle). See
Lua memory
management (on page 6-31) for more information.
gcinfo() Returns the number of kilobytes of dynamic memory that TSP is
using and the current garbage collector threshold (also in Kbytes).
See
Lua memory management (on page 6-31) for more information.
print(e1, e2, ...) Receives any number of arguments, and generates a response
message, using the
tostring
function to convert them to strings.
The output is not formatted. For formatted output, you can use the
string.format
command (see String library functions (on page 6-
31)).
tonumber(x)
tonumber(x ,base)
Returns
x
converted to a number. If x is already a number, or a
convertible string, then the number is returned; otherwise, it returns
nil
.
An optional argument specifies the base to interpret the numeral.
The base may be any integer between 2 and 36, inclusive. In bases
above 10, the letter
A
(in either upper or lower case) represents 10,
B
represents 11, and so forth, with
Z
representing 35. In base 10,
the default, the number may have a decimal part, as well as an
optional exponent. In other bases, only unsigned integers are
accepted.
tostring(x) Receives an argument of any type and converts it to a string in a
reasonable format.
type(v)
The possible results of this function are
"nil"
(a string, not the
value nil),
number
,
string
,
Boolean
,
table
,
function
,
thread
, and
userdata
.