Passerr Catalog; Pause Catalog - Texas Instruments TI-89 Manual Book

The example Program Editor function to the
right uses
implement symbolic differentiation. Studying
and completing this function can help teach
you how to differentiate manually. You could
even include functions that the
TI-89 / TI-92 Plus cannot differentiate, such
as Bessel functions.
PassErr
CATALOG
PassErr
Passes an error to the next level.
If "errornum" is zero,
anything.
The
Else
ClrErr or
processed or ignored, use
do with the error is not known, use
to send it to the next error handler. (See also
.)
ClrErr
Pause
CATALOG
Pause [expression]
Suspends program execution. If you include
expression
I/O screen.
expression
such as
4DD
operator to perform unit and number base
conversions.
If the result of
single screen, you can use the cursor pad to
scroll the display.
Program execution resumes when you
press ¸.
and to partially
getType() part()
PassErr does not do
clause in the program should use
PassErr . If the error is to be
. If what to
ClrErr
, displays on the Program
expression
can include conversion operations
. You can also use the 4
and
4Rect
is too big to fit on a
expression
:d(y,x)
:Func
:Local f
:If getType(y)="VAR"
: Return when(y=x,1,0,0)
:If part(y)=0
: Return 0 ¦ y=p,ˆ,i,numbers
:part(y,0)! f
:If f="L" ¦ if negate
: Return ë d(part(y,1),x)
:If f=" " ¦ if minus
: Return d(part(y,1),x)
ì d(part(y,2),x)
:If f="+"
: Return d(part(y,1),x)
+d(part(y,2),x)
:If f="ù "
: Return
part(y,1)ù d(part(y,2),x)
+part(y,2)ù d(part(y,1),x)
:If f="{"
: Return seq(d(part(y,k),x),
k,1,part(y))
:Return undef
:EndFunc
See program listing example.
ClrErr
PassErr
Program segment:
©
:ClrIO
:DelVar temp
:1"temp[1]
:1"temp[2]
:Disp temp[2]
:¦ Guess the Pattern
:For i,3,20
: temp[iì2]+temp[iì1]"temp[i]
: Disp temp[i]
: Disp temp,"Can you guess the
next","number?"
: Pause
:EndFor
©
Appendix A: Functions and Instructions 479