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# soshial/LKS-92.py

Last active Apr 12, 2020
EPSG:3059 (LKS-92) koordināšu pārrēķins uz platuma un garuma grādiem; transform coordinates code
 import math def lks_2_latlon(x, y): # Ellipsoid model constants (actual values here are for WGS84) */ UTMScaleFactor = 0.9996 sm_a = 6378137.0 sm_b = 6356752.314 x -= 500000.0 # Pirmā atšķirība no WGS84 - Kilometriņš šurpu, kilometriņš turpu. # Ja šis nedod korektu rezultātu, atkomentē sekojošo rindiņu. # y -= -6000000.0 x /= UTMScaleFactor y /= UTMScaleFactor # Otrā atšķirība no WGS84 - Centrālais meridiāns ir citur. lambda0 = math.radians(24) # Precalculate n (Eq. 10.18) */ n = (sm_a - sm_b) / (sm_a + sm_b) # Precalculate alpha_ (Eq. 10.22) */ # (Same as alpha in Eq. 10.17) */ alpha_ = ((sm_a + sm_b) / 2.0) * (1 + (pow(n, 2.0) / 4) + (pow(n, 4.0) / 64)) # Precalculate y_ (Eq. 10.23) */ y_ = y / alpha_ # Precalculate beta_ (Eq. 10.22) */ beta_ = (3.0 * n / 2.0) + (-27.0 * pow(n, 3.0) / 32.0) + (269.0 * pow(n, 5.0) / 512.0) # Precalculate gamma_ (Eq. 10.22) */ gamma_ = (21.0 * pow(n, 2.0) / 16.0) + (-55.0 * pow(n, 4.0) / 32.0) # Precalculate delta_ (Eq. 10.22) */ delta_ = (151.0 * pow(n, 3.0) / 96.0) + (-417.0 * pow(n, 5.0) / 128.0) # Precalculate epsilon_ (Eq. 10.22) */ epsilon_ = (1097.0 * pow(n, 4.0) / 512.0) # Now calculate the sum of the series (Eq. 10.21) */ phif = y_ + (beta_ * math.sin(2.0 * y_)) + (gamma_ * math.sin(4.0 * y_)) + (delta_ * math.sin(6.0 * y_)) + (epsilon_ * math.sin(8.0 * y_)) # Precalculate ep2 */ ep2 = (pow(sm_a, 2.0) - pow(sm_b, 2.0)) / pow(sm_b, 2.0) # Precalculate cos (phif) */ cf = math.cos(phif) # Precalculate nuf2 */ nuf2 = ep2 * pow(cf, 2.0) # Precalculate Nf and initialize Nfpow */ Nf = pow(sm_a, 2.0) / (sm_b * math.sqrt(1 + nuf2)) Nfpow = Nf # Precalculate tf */ tf = math.tan(phif) tf2 = tf * tf tf4 = tf2 * tf2 # Precalculate fractional coefficients for x**n in the equations # below to simplify the expressions for latitude and longitude. */ x1frac = 1.0 / (Nfpow * cf) Nfpow *= Nf # /* now equals Nf**2) */ x2frac = tf / (2.0 * Nfpow) Nfpow *= Nf # /* now equals Nf**3) */ x3frac = 1.0 / (6.0 * Nfpow * cf) Nfpow *= Nf # /* now equals Nf**4) */ x4frac = tf / (24.0 * Nfpow) Nfpow *= Nf # /* now equals Nf**5) */ x5frac = 1.0 / (120.0 * Nfpow * cf) Nfpow *= Nf # /* now equals Nf**6) */ x6frac = tf / (720.0 * Nfpow) Nfpow *= Nf # /* now equals Nf**7) */ x7frac = 1.0 / (5040.0 * Nfpow * cf) Nfpow *= Nf # /* now equals Nf**8) */ x8frac = tf / (40320.0 * Nfpow) # Precalculate polynomial coefficients for x**n. # -- x**1 does not have a polynomial coefficient. */ x2poly = -1.0 - nuf2 x3poly = -1.0 - 2 * tf2 - nuf2 x4poly = 5.0 + 3.0 * tf2 + 6.0 * nuf2 - 6.0 * tf2 * nuf2 - 3.0 * (nuf2 * nuf2) - 9.0 * tf2 * (nuf2 * nuf2) x5poly = 5.0 + 28.0 * tf2 + 24.0 * tf4 + 6.0 * nuf2 + 8.0 * tf2 * nuf2 x6poly = -61.0 - 90.0 * tf2 - 45.0 * tf4 - 107.0 * nuf2 + 162.0 * tf2 * nuf2 x7poly = -61.0 - 662.0 * tf2 - 1320.0 * tf4 - 720.0 * (tf4 * tf2) x8poly = 1385.0 + 3633.0 * tf2 + 4095.0 * tf4 + 1575 * (tf4 * tf2) # /* Calculate latitude */ lat = phif + x2frac * x2poly * (x * x) + x4frac * x4poly * pow(x, 4.0) + x6frac * x6poly * pow(x, 6.0) + x8frac * x8poly * pow(x, 8.0) # /* Calculate longitude */ lon = lambda0 + x1frac * x + x3frac * x3poly * pow(x, 3.0) + x5frac * x5poly * pow(x, 5.0) + x7frac * x7poly * pow(x, 7.0) return math.degrees(lat), math.degrees(lon) LKS_UTM_SCALE_FACTOR = 0.9996 def latlon_2_lks(lat, lon): lat = math.radians(lat) lon = math.radians(lon) # /* Ellipsoid model constants (actual values here are for GRS80) */ sm_a = 6378137.0 sm_b = 6356752.314140 xy = [] # // lks_MapLatLonToXY (lat, lon, lks_UTMCentralMeridian (zone), xy) phi = lat lambda_ = lon lambda0 = math.radians(24) # /* Precalculate ep2 */ ep2 = (sm_a * sm_a - sm_b * sm_b) / sm_b / sm_b # /* Precalculate nu2 */ nu2 = ep2 * math.cos(phi) * math.cos(phi) # /* Precalculate N */ N = sm_a * sm_a / (sm_b * math.sqrt(1 + nu2)) # /* Precalculate t */ t = math.tan(phi) t2 = t * t # /* Precalculate l */ l = lambda_ - lambda0 # /* Precalculate coefficients for l**n in the equations below # so a normal human being can read the expressions for easting # and northing # -- l**1 and l**2 have coefficients of 1.0 */ l3coef = 1.0 - t2 + nu2 l4coef = 5.0 - t2 + 9 * nu2 + 4.0 * (nu2 * nu2) l5coef = 5.0 - 18.0 * t2 + (t2 * t2) + 14.0 * nu2 - 58.0 * t2 * nu2 l6coef = 61.0 - 58.0 * t2 + (t2 * t2) + 270.0 * nu2 - 330.0 * t2 * nu2 l7coef = 61.0 - 479.0 * t2 + 179.0 * (t2 * t2) - (t2 * t2 * t2) l8coef = 1385.0 - 3111.0 * t2 + 543.0 * (t2 * t2) - (t2 * t2 * t2) # /* Calculate easting (x) */ x = N * math.cos(phi) * l + (N / 6.0 * pow(math.cos(phi), 3.0) * l3coef * pow(l, 3.0)) + ( N / 120.0 * pow(math.cos(phi), 5.0) * l5coef * pow(l, 5.0)) + (N / 5040.0 * pow(math.cos(phi), 7.0) * l7coef * pow(l, 7.0)) # /* Calculate northing (y) */ y = lks_arc_length_of_meridian(phi) + (t / 2.0 * N * pow(math.cos(phi), 2.0) * pow(l, 2.0)) + ( t / 24.0 * N * pow(math.cos(phi), 4.0) * l4coef * pow(l, 4.0)) + (t / 720.0 * N * pow(math.cos(phi), 6.0) * l6coef * pow(l, 6.0)) + ( t / 40320.0 * N * pow(math.cos(phi), 8.0) * l8coef * pow(l, 8.0)) x = x * LKS_UTM_SCALE_FACTOR + 500000.0 # Ja šis nedod korektu rezultātu, pamēģiniet noņemt 6000000 vai 10000000 # Ja jums izdosies, lūdzu pierakstiet komentāros y = y * LKS_UTM_SCALE_FACTOR - 6000000.0 if y < 0.0: y = y + 10000000.0 return x, y def lks_arc_length_of_meridian(phi): # /* Precalculate n */ sm_a = 6378137.0 sm_b = 6356752.314140 n = (sm_a - sm_b) / (sm_a + sm_b) # /* Precalculate alpha */ alpha = ((sm_a + sm_b) / 2.0) * (1.0 + (pow(n, 2.0) / 4.0) + (pow(n, 4.0) / 64.0)) # /* Precalculate beta */ beta = (-3.0 * n / 2.0) + (9.0 * pow(n, 3.0) / 16.0) + (-3.0 * pow(n, 5.0) / 32.0) # /* Precalculate gamma */ gamma = (15.0 * pow(n, 2.0) / 16.0) + (-15.0 * pow(n, 4.0) / 32.0) # /* Precalculate delta */ delta = (-35.0 * pow(n, 3.0) / 48.0) + (105.0 * pow(n, 5.0) / 256.0) # /* Precalculate epsilon */ epsilon = (315.0 * pow(n, 4.0) / 512.0) # /* Now calculate the sum of the series and return */ result = alpha * (phi + (beta * math.sin(2.0 * phi)) + (gamma * math.sin(4.0 * phi)) + (delta * math.sin(6.0 * phi)) + (epsilon * math.sin(8.0 * phi))) return result

### soshial commented Apr 12, 2020 • edited

 This is a Python adaptation of PHP code written by @laacz: https://gist.github.com/laacz/2597627 Links to check conversion: