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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: 98,049

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: 98,049

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: 98,049

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: 98,049

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: 98,049

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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**If it ain't broke, fix it until it is.**

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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: 98,049

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: 98,049

i am not getting

Do you know what an array is?

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**If it ain't broke, fix it until it 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'

'But our love is like the wind. I can't see it but I can feel it.' -A Walk to remember

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**anonimnystefy****Real Member**- From: Harlan's World
- Registered: 2011-05-23
- Posts: 15,954

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
- Posts: 98,049

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
- Posts: 98,049

Do you know how to access an individual array element?

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**If it ain't broke, fix it until it is.**

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 98,049

What is pg?

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