Radar_coordinates

radar_coords.py

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   "source": [
    "import pyproj\n",
    "import numpy as np\n",
    "import math"
   ]
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   "cell_type": "markdown",
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   "source": [
    "### 1. Corner coordinates approach"
   ]
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   "source": [
    "# convert corners in lat/lon degrees to provided projection (RD)\n",
    "\n",
    "# geographic_geo_product_corners\n",
    "coords = [[0, 49.362053],\n",
    "          [0, 55.973602],\n",
    "          [10.856429, 55.388977],\n",
    "          [9.0092793, 48.895298]]\n",
    "\n",
    "lons, lats = list(zip(*coords))\n",
    "\n",
    "inproj4 = '+proj=stere +lat_0=90 +lon_0=0 +lat_ts=60 +a=6378.14 +b=6356.75 +x_0=0 y_0=0'\n",
    "\n",
    "crobj = pyproj.Proj(inproj4)\n",
    "mapx, mapy = crobj(lons, lats, inverse=False)\n",
    "\n",
    "ulx = mapx[1]\n",
    "lrx = mapx[3]\n",
    "uly = mapy[1]\n",
    "lry = mapy[3]\n",
    "\n",
    "ulx, uly, lrx, lry"
   ]
  },
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   "cell_type": "markdown",
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   "source": [
    "### 2. Pixel calculation"
   ]
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   "source": [
    "# geographic_geo_pixel_size_x\n",
    "yres = -1.0000052 # km\n",
    "xres = 1.0000013\n",
    "\n",
    "# geographic_geo_column_offset\n",
    "xoffset = 0\n",
    "yoffset = 3649.9802\n",
    "\n",
    "# geographic_geo_number_columns\n",
    "ncol = 700\n",
    "nrow = 765\n",
    "\n",
    "ulx = xoffset * math.copysign(1, xres)\n",
    "uly = yoffset * math.copysign(1, yres)\n",
    "uly = yoffset * yres\n",
    "lrx = ulx + ncol * xres\n",
    "lry = uly + nrow * yres"
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   "source": [
    "ulx, uly, lrx, lry"
   ]
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   "execution_count": 27,
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   "source": [
    "# geographic_geo_pixel_size_x\n",
    "yres = -1.0000052 * 0.5 # km\n",
    "xres = 1.0000013 * 0.5\n",
    "\n",
    "# geographic_geo_column_offset\n",
    "xoffset = 0\n",
    "yoffset = 3649.9802*2\n",
    "\n",
    "# geographic_geo_number_columns\n",
    "ncol = 700*2\n",
    "nrow = 765*2\n",
    "\n",
    "ulx = xoffset * xres\n",
    "uly = yoffset * yres\n",
    "lrx = ulx + ncol * xres\n",
    "lry = uly + nrow * yres"
   ]
  },
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   "cell_type": "code",
   "execution_count": 24,
   "metadata": {
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     "execution_count": 24,
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   "source": [
    "ulx, uly, lrx, lry"
   ]
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