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Where the constants
and
k σ are specified in Table 1 according to
δ
,
m
k
which functions are being computed.
Table 1
Function
m
Initial constants
Result
σ
δ
k
k
Multiplication 0
k − 2
0 0 , zx given,
≈
) sgn( k z
0 0 yx y
n
0 = y
0
Division
0
k − 2
x y
0 0 , yx given,
−
sgn(
)
y
0
≈
k
z
n
0
0 = z
0
Sine
and
1
≈
θ
sin cos
y x
, θ = = zA x
k − − 2 tan 1
) sgn( k z
,
n
0
0
cosine
≈
θ
n
0 = y
0
Inverse tangent
1
0 0 , yx given,
−
k − − 2 tan 1
x y
sgn(
)
y
−
0 1
k
≈
tan
z
n
0
0 = z
0
Hyperbolic sine cosine, exponential Hyperbolic inverse tangent, square root
-1
≈
θ
sinh cosh
x
, θ = = zB x n
k − − 2 tanh 1
) sgn( k z
,
0
0
and
≈
θ
y
n
0 = y
0
θ
+ ≈
y x e
n
n
-1
x y
0 0 , yx given,
−
k − − 2 tanh 1
sgn(
)
y
−
0 1
≈
tanh
z
k
n
0
0 = z
0
2
2
−
y x
0
0
≈
x
n
B
n
n
0 ∏ = j
0 ∏ = j
Where
and
) σ are pre-stored constants.
σ
=
=
cos(
)
cosh(
A
B
j
j
To illustrate how the CORDIC method works consider the following division example. Suppose we wish to calculate 6.4 divided by 4. It follows from Table 1 that
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