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authorIndrajith K L2022-12-03 17:00:20 +0530
committerIndrajith K L2022-12-03 17:00:20 +0530
commitf5c4671bfbad96bf346bd7e9a21fc4317b4959df (patch)
tree2764fc62da58f2ba8da7ed341643fc359873142f /v_windows/v/vlib/math/tan.v
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Adds most of the toolsHEADmaster
Diffstat (limited to 'v_windows/v/vlib/math/tan.v')
-rw-r--r--v_windows/v/vlib/math/tan.v113
1 files changed, 113 insertions, 0 deletions
diff --git a/v_windows/v/vlib/math/tan.v b/v_windows/v/vlib/math/tan.v
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+++ b/v_windows/v/vlib/math/tan.v
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+module math
+
+const (
+ tan_p = [
+ -1.30936939181383777646e+4,
+ 1.15351664838587416140e+6,
+ -1.79565251976484877988e+7,
+ ]
+ tan_q = [
+ 1.00000000000000000000e+0,
+ 1.36812963470692954678e+4,
+ -1.32089234440210967447e+6,
+ 2.50083801823357915839e+7,
+ -5.38695755929454629881e+7,
+ ]
+ tan_dp1 = 7.853981554508209228515625e-1
+ tan_dp2 = 7.94662735614792836714e-9
+ tan_dp3 = 3.06161699786838294307e-17
+ tan_lossth = 1.073741824e+9
+)
+
+// tan calculates tangent of a number
+pub fn tan(a f64) f64 {
+ mut x := a
+ if x == 0.0 || is_nan(x) {
+ return x
+ }
+ if is_inf(x, 0) {
+ return nan()
+ }
+ mut sign := 1 // make argument positive but save the sign
+ if x < 0 {
+ x = -x
+ sign = -1
+ }
+ if x > math.tan_lossth {
+ return 0.0
+ }
+ // compute x mod pi_4
+ mut y := floor(x * 4.0 / pi) // strip high bits of integer part
+ mut z := ldexp(y, -3)
+ z = floor(z) // integer part of y/8
+ z = y - ldexp(z, 3) // y - 16 * (y/16) // integer and fractional part modulo one octant
+ mut octant := int(z) // map zeros and singularities to origin
+ if (octant & 1) == 1 {
+ octant++
+ y += 1.0
+ }
+ z = ((x - y * math.tan_dp1) - y * math.tan_dp2) - y * math.tan_dp3
+ zz := z * z
+ if zz > 1.0e-14 {
+ y = z + z * (zz * (((math.tan_p[0] * zz) + math.tan_p[1]) * zz + math.tan_p[2]) / ((((zz +
+ math.tan_q[1]) * zz + math.tan_q[2]) * zz + math.tan_q[3]) * zz + math.tan_q[4]))
+ } else {
+ y = z
+ }
+ if (octant & 2) == 2 {
+ y = -1.0 / y
+ }
+ if sign < 0 {
+ y = -y
+ }
+ return y
+}
+
+// tanf calculates tangent. (float32)
+[inline]
+pub fn tanf(a f32) f32 {
+ return f32(tan(a))
+}
+
+// tan calculates cotangent of a number
+pub fn cot(a f64) f64 {
+ mut x := a
+ if x == 0.0 {
+ return inf(1)
+ }
+ mut sign := 1 // make argument positive but save the sign
+ if x < 0 {
+ x = -x
+ sign = -1
+ }
+ if x > math.tan_lossth {
+ return 0.0
+ }
+ // compute x mod pi_4
+ mut y := floor(x * 4.0 / pi) // strip high bits of integer part
+ mut z := ldexp(y, -3)
+ z = floor(z) // integer part of y/8
+ z = y - ldexp(z, 3) // y - 16 * (y/16) // integer and fractional part modulo one octant
+ mut octant := int(z) // map zeros and singularities to origin
+ if (octant & 1) == 1 {
+ octant++
+ y += 1.0
+ }
+ z = ((x - y * math.tan_dp1) - y * math.tan_dp2) - y * math.tan_dp3
+ zz := z * z
+ if zz > 1.0e-14 {
+ y = z + z * (zz * (((math.tan_p[0] * zz) + math.tan_p[1]) * zz + math.tan_p[2]) / ((((zz +
+ math.tan_q[1]) * zz + math.tan_q[2]) * zz + math.tan_q[3]) * zz + math.tan_q[4]))
+ } else {
+ y = z
+ }
+ if (octant & 2) == 2 {
+ y = -y
+ } else {
+ y = 1.0 / y
+ }
+ if sign < 0 {
+ y = -y
+ }
+ return y
+}