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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: 94,482

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

**In mathematics, you don't understand things. You just get used to them.**

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

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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: 94,482

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?

**In mathematics, you don't understand things. You just get used to them.**

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

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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: 94,482

Hi;

Is it continuous?

**In mathematics, you don't understand things. You just get used to them.**

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

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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: 94,482

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

**In mathematics, you don't understand things. You just get used to them.**

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

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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: 94,482

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.

**In mathematics, you don't understand things. You just get used to them.**

**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: 94,482

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.

**In mathematics, you don't understand things. You just get used to them.**

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

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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
- Posts: 94,482

Putting a zero in the array element.

**In mathematics, you don't understand things. You just get used to them.**

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

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

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 94,482

i am not getting

Do you know what an array is?

**In mathematics, you don't understand things. You just get used to them.**

**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'

'You have made another human being happy. There is no greater accomplishment.' -bobbym

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 15,919

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: 94,482

He can not do that yet.

**In mathematics, you don't understand things. You just get used to them.**

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

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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: 94,482

Do you know how to access an individual array element?

**In mathematics, you don't understand things. You just get used to them.**

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

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 94,482

What is pg?

**In mathematics, you don't understand things. You just get used to them.**

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

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