The
program Sequen86 plots one recursive sequence with one initial
condition. The function is stored in variable y1, with x presenting
y1(n-1). The
initial condition is assumed to be y1(1).
This
program was originally posted on ticalc.org on April 28, 2001. Link:
https://www.ticalc.org/archives/files/fileinfo/186/18667.html
18
years, wow, how time flies.
TI-86
Program Sequen86
(354
bytes)
Func
FnOff
PlOff
ClLCD
DelVar(L1)
DelVar(L2)
Outpt(6,1,”Let
y1 = u”)
Outpt(7,1,”Let
x = n-1”)
InpSt
“y1 =”, Y
St>Eq(Y,y1)
Input
“Initial Cond: “,I
Input
“# of Steps: “,S
{I}
→ U
For(N,
dimL U+1, S+1, 1)
y1(U(N-1))
→ U(N)
End
seq(x,x,1,S+1)
→ L1
U
→ L2
0
→ xMin
S+1
→ xMax
min(U)
– 1 → yMin
max(U)
+ 1 → yMax
Plot1(1,L1,L2)
FnOff
1
Disp
“L1 = n”
Pause
“L2 = u”
DispG
Example:
u(n)
= u(n-1)/3 + 1/4
Initial
condition, u(1) = 1/5
Number
of Steps: 10
Set
up for Sequen86:
y1
= x/3 + 1/4
The
2019 Version
Here
is an alternate version, SEQGRAPH. Use
U for U(n-1) and N for n. The program allows the initial condition
for any value of N.
TI-86
Program SEQGRAPH
(277
bytes)
InpSt
“U1(U,N) = “,S1
St>Eq(S1,U1)
Input
“N Start = “,N
Input
“U0 = “,U
Input
“Steps: “,S
S
+ 1 → dimL xList
S
+ 1 → dimL yList
N
→ xList(1)
U
→ yList(1)
For(I,
2, S+1)
xList(I-1)
+ 1 → N
N
→ xList(I)
yList(I-1)
→ U
U1
→ yList(I)
End
FnOff
PlOff
PlOn
1
Plot1(1,xList,yList)
ZData
Example:
u(n)
= u(n-1)/3 + 1/4
Initial
condition, u(1) = 1/5
Number
of Steps: 10
Set
up for SEQGRAPH:
U1
= U/3 + 1/4
N
Start: 1
U0
= 1/5 (initial condition)
Eddie
All
original content copyright, © 2011-2019. Edward Shore.
Unauthorized use and/or unauthorized distribution for commercial
purposes without express and written permission from the author is
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