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Procedure: Clear Statistic Register on each new problem

f [∑]
n [R/S] display Data Count
Enter Data [R/S] display 1, 2, 3,....,n
0 [R/S] display β [R/S] ϴ // input 0 "Activate Final Calculations"

β value type of failure meaning
β < 1 infant mortality high probability of failing at early stages
β =1 random failures failures are independent of time
1 < β < 4 early wear out can be due to generic failure modes, such as corrosion
β > 4 rapid wear out steep curve with fast wear out at some point

Example: f [∑] [FIX] 2
Xi: 34, 60, 75, 95, 119, 158 (hours to failure)
(Xi's must be entered in incresing order.)
n=6
β=1.95
ϴ=104.09

f [∑]
6 [R/S] display 6.00
34 [R/S] display 1.00
60 [R/S] display 2.00
75 [R/S] display 3.00
95 [R/S] display 4.00
119 [R/S] display 5.00
158 [R/S] display 6.00

0 [R/S] display answer 1.95 [R/S] display answer 104.09

Program:
Code:

01 STO 7
02  1
03 STO 0
04 X<>Y
05 R/S
06 X=0
07 GTO 28
08 LN
09 RCL 0
10  .
11  3
12  -
13 RCL 7
14  .
15  4
16  +
17  ÷
18  1
19 STO+0
20 X<>Y
21  -
22 1/x
23 LN
24 LN
25 X<>Y
26 ∑+
27 GTO 05
28  1
29  ŷ,r
30  0
31  ŷ,r 
32 X<>Y
33 R↓
34  -
35 LSTx
36 X<>Y
37 R/S
38  ÷
39 CHS
40 e^x
41 GTO 00

Remark:
This program used the [L.R.] function on
program line between 28 - 35

Gamo 2/2020
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