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**prathima****Member**- Registered: 2013-09-19
- Posts: 33

i need scilab progam for

1. to obtain fibonacci series

2.to obtain non fibonacci series

3. to find the root of the equation f(x,a)=a*cos(x)-x*e(-a*x) for different values of a∈[1,10]

please reply soon.

it is imporant for my exams

*Last edited by prathima (2013-12-31 17:27:06)*

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 102,296

I do not program in Scilab. Best I can do is pseudocode, you will and should write them.

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**prathima****Member**- Registered: 2013-09-19
- Posts: 33

ok....

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 102,296

1. to obtain fibonacci series

I guess you mean Fibonacci sequence.

1) x1 = 1;

2) x2 = 1;

3) h = x2;

4) x2 = x1 + x2;

5)Print[x2]

5) x1 = h;

6) Goto 3

Remember to debug it if necessary. I am partying.

2.to obtain non fibonacci series

What is a non Fibonacci sequence specifically?

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**prathima****Member**- Registered: 2013-09-19
- Posts: 33

non fibonacci sequence is 4,6,7,9.10,11,12,14,15,16,17,18,19,20,...

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**gAr****Member**- Registered: 2011-01-09
- Posts: 3,479

The example for Fibonacci is there: http://hkumath.hku.hk/~nkt/Scilab/IntroToScilab.html

for 3, you can use newton-raphson,

E.g. in python,

```
from math import exp, sin, cos
t=3
told=1
a=5
while abs(t-told) > 0.00000000001:
told=t
t=t - (a*cos(t) - t*exp(-a*t))/(a*t*exp(-a*t) - a*sin(t) - exp(-a*t))
print t
```

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**prathima****Member**- Registered: 2013-09-19
- Posts: 33

i dnt knw hw to insert the condition that a∈[1,10] in newton raphson method

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 102,296

Hi;

Is it continuous?

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**prathima****Member**- Registered: 2013-09-19
- Posts: 33

i dont know.

in question it is not clear that a is continous or not

*Last edited by prathima (2014-01-01 01:06:38)*

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 102,296

What values can a take? a = 1,2,3,4... integers? Or any value from 1 to 10 like 7.27?

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**prathima****Member**- Registered: 2013-09-19
- Posts: 33

question is

scilab program to find the root of eqn f(x,a)=a*cos(x)-x*e^(-a*x) for different values of a∈[1,10]

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 102,296

Why not use the code gAr provided for python.

```
from math import exp, sin, cos
t=3
told=1
input[a];
while abs(t-told) > 0.00000000001:
told=t
t=t - (a*cos(t) - t*exp(-a*t))/(a*t*exp(-a*t) - a*sin(t) - exp(-a*t))
print t
```

I just changed one line to Input[a]. Now you can enter any a you want.

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**prathima****Member**- Registered: 2013-09-19
- Posts: 33

thank you:)

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**prathima****Member**- Registered: 2013-09-19
- Posts: 33

scilab program to obtain non fibonacci series

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 102,296

Generate the fibonacci numbers like I did in the first post and then an array of {1,2,3,4,5....}. When you get a fibonacci number cross it out by zeroing the array element.

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**prathima****Member**- Registered: 2013-09-19
- Posts: 33

zeroing the array element means

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
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Putting a zero in the array element.

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prathima wrote:

it is imporant for my exams

I hope you do not mind me asking but what grade student are you?

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 102,296

i am not getting

Do you know what an array is?

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'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

I'm not crazy, my mother had me tested.

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**anonimnystefy****Real Member**- From: Harlan's World
- Registered: 2011-05-23
- Posts: 16,000

Hi prathima

Basically, just take the array {1,2,3,4,5,6,...} and put a zero instead all the numbers which are Fibonacci numbers.

*Last edited by anonimnystefy (2014-01-01 02:00:47)*

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
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He can not do that yet.

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**prathima****Member**- Registered: 2013-09-19
- Posts: 33

in scilab array set values in vector form for ex. A=[1 2 3]

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
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Do you know how to access an individual array element?

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 102,296

What is pg?

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