Texas Instruments TI-92+, Список советов

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While TI Basic is particularly suited for quick, short programs and functions, it is certainly possible to
use it to code significant applications: Roberto Perez-Franco's symbolic circuit simulator Symbulator is
one good example. Applications which require maximum speed and fine control of the keyboard and
display, as well as access to system functions, are best coded in C.
If you want to learn calculator programming, TI Basic is a good place to start, comments of Raymond
and Dijkstra notwithstanding. You will get working results faster than trying to learn C if you have never
programmed before. You may find that TI Basic is all you need. If not, it will be easier to learn C once
you have some TI Basic experience.
[7.39] Quickly delete locked, archived variables
Two steps are required to delete an archived variable: first you unarchive the variable, then delete it. If
the variable is also locked, three steps are required. These steps are necessary whether you use the
functions unlock() and unarchiv(), or use the VAR-LINK screen. This simple program deletes any
variable or list of variables, regardless of whether they are archived or locked.
delvar 1 (n)
Prgm
©("v"), ({"v",...}) Delete v locked/archived
©26dec0
1 /dburkett@infinet.com
local k © Loop counter
If getType(n)="STR" © Convert single argument to list
{n} → n
If getType(n)="LIST" then © Delete list of variables
for k, 1 ,dim(n)
if getType(#(n[k])) ≠ "NONE" then © Ignore nonexistent variables
try:unarchiv #(n[k]):else:endtry © Must unarchive before unlocking
try:unlock #(n[k]):else:endtry
delvar #(n[k])
endif
endfor
else
© Display argument type error
dialog
title "DELVAR
1 "
text "Bad argument type"
endDlog
endif
EndPrgm
The variable name argument is a string or list of strings. To delete a single variable var, use
delvar 1 ("var")
To delete more than one variable, use a list:
delvar 1 ({"var 1 ","var2","var3"})
A single string argument is first converted to a list, so either argument type is handled consistently,
which saves some program memory. Variables which do not exist are ignored. This may not be the
most appropriate behavior, but at least it is consistent with the behavior of unarchiv(), unlock() and
delvar(). An error message is displayed in a dialog box if the argument is neither a string nor a list.
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