How to calculate the Sine ?

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Heeey ! I'm implement CORDIC right now in the server XD. The algoithm :

Code:

Cordic2(z)
Func{
  Local angle,x,y,temp,s,i
  {.7854,.46365,.24498,.12435,.06242,.03124,.01562,.00781,.00391,.00195,9.8–
ª4,4.9–ª4,2.4–ª4,1.2–ª4,6.–ª5}»angle
  0.60725»x
  0»y

  For i,0,14
    when(z=0,1,signe(z))»s
    x-s*y/2^i»temp
    y+s*x/2^i»y
    temp»x
    z-s*angle[i+1]»z
  EndFor

  Return {x,y}
EndFunc

This algo return the cos(=x) value AND the sin(=y) value ! The next algo do it, too.

And my version, to get a result between 0 and 255.

Code:

CORDIC255
1   VARIABLES
2     x EST_DU_TYPE NOMBRE
3     y EST_DU_TYPE NOMBRE
4     temp EST_DU_TYPE NOMBRE
5     s EST_DU_TYPE NOMBRE // this is the sign to change the - in +. so s = 1 or -1.
6     i EST_DU_TYPE NOMBRE
7     angle EST_DU_TYPE LISTE
8     z EST_DU_TYPE NOMBRE (z = input angle, in °)
9   DEBUT_ALGORITHME
10    LIRE z // z = angle
11    z PREND_LA_VALEUR z*2 //to increase the accuracy
12    angle[0] PREND_LA_VALEUR 90
13    angle[1] PREND_LA_VALEUR 53
14    angle[2] PREND_LA_VALEUR 28
15    angle[3] PREND_LA_VALEUR 14
16    angle[4] PREND_LA_VALEUR 7
17    angle[5] PREND_LA_VALEUR 3
18    angle[6] PREND_LA_VALEUR 2
19    angle[7] PREND_LA_VALEUR 1
20    //*end const*
21    x PREND_LA_VALEUR 155
22    y PREND_LA_VALEUR 0
23    //for
24    POUR i ALLANT_DE 0 A 7
25      DEBUT_POUR
26      SI (z==0) ALORS
27        DEBUT_SI
28        s PREND_LA_VALEUR 1
29        FIN_SI
30        SINON
31          DEBUT_SINON
32          s PREND_LA_VALEUR z/abs(z)
33          FIN_SINON
34      temp PREND_LA_VALEUR x - s*(round(y/pow(2,i)))
35      y PREND_LA_VALEUR y + s*(round(x/pow(2,i)))
36      x PREND_LA_VALEUR temp
37      z PREND_LA_VALEUR z - s*(angle[i])
38      FIN_POUR
39    AFFICHER "x cos = "
40    AFFICHER x
41    AFFICHER "y sin = "
42    AFFICHER y
43  FIN_ALGORITHME

Sorry for french XD
(si = if, alors = then, sinon = else, pour = for, prend_la_valeur = ':=' OR '=', afficher = print() ). I've made this with Algobox.

And where I am now :



And I have to make the state machine, too.

The precision (of my algo) is ± "1°" (when you take the inverse function). (for ±, do alt + 0177 ^^).

I've join CORDIC255, this is an example of the algorithm. Cordic2 is the file where I've found the first algorithm.