Taylor series with sin(x).... I need help setting up my while loop and error bound

My question is here: http://i.imgur.com/EkSTC0x.png?1

This is what I have so far....it is not giving me anything, and I know there are things wrong with it, but I am not sure what: ---------------------

a picture of my script file is here: http://i.imgur.com/RFoX9y8.png?1

---------------------- Thank you!

Answer 1

[Roger Stafford]

I see three mistakes here.

1. You reference sin_approx(count-1) but you aren't storing sin_approx in an array so there is no such entity. You need to either create an array or else create a temporary "previous" value.

2. You ask for the angle in degrees but your series expansion is only good for radian measure.

3. The inequality in the while loop is in the wrong direction. You need

 while abs(E)>=0.000001

[Lemmiwinks]

Ok, so if, prior to my loop commands, I define sin_approx=[-2*pi:0.001:2*pi], change the E<= to E>=, and somewhere in my commands convert the inputted angle to radians (the specifications require an angle input in degrees) and then reconvert the result back to degrees, it should be fixable?

[Lemmiwinks]

and thanks for the answer

[Image Analyst]

There is a sind() function that takes arguments in degrees, so sind(45) is the same value as sin(45*pi/180).

[Lemmiwinks]

Do I need to use the sin MATLAB function in my script though? I thought the program is approximating that.. Also, after everything has looped and stopped, how can I output the result for the approximated sin(x)? I tried this way but I get a long string of numbers:

fprintf('sin(x) = %5.4f',sin_approx)

[Roger Stafford]

Yes, you do need to convert to radians because that is what the Taylor series assumes. It would be invalid for angles in degrees. The Taylor series for 'sind' is altogether different.

Answer 2

[sanjeeb]

I writen above mention like below

clc

x=input('Enter the value of x in degree: ');

xr=x*pi/180;

n=0;

s=0;

while err>=0.000001

a=(-1)^n*(xr)^(2*n+1)/factorial(2*n+1);

s=s+a;

err=abs(a/s);

n=n+1;

end

fprintf('The value of taylor series sinx %f for specific value of x %f',s,x)

fprintf('The value of MATLAB function sindx %f for specific value of x %f',sind(x))

but it shown error as per below

Undefined function or variable 'err'.

Error in Practice2 (line 7)

while err>=0.000001

Please correct it