Testing the possibility of xarray dot product of two DataArrays along their shared dims.

xarray_correlation_testing.ipynb

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      "cell_type": "code",
      "source": "import xarray as xr\nimport numpy as np\nimport xarray.ufuncs as xrf",
      "execution_count": 172,
      "outputs": []
    },
    {
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      "source": "da_vals = np.arange(6 * 5 * 4 * 3).reshape((6, 5, 4, 3))\nda = xr.DataArray(da_vals, dims=['x', 'y', 'z', 't'])\ndm_vals = np.arange(3)\ndm = xr.DataArray(dm_vals, dims=['t'])",
      "execution_count": 173,
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      "cell_type": "code",
      "source": "np.cov(da_vals[1,0,:] , dm_vals)",
      "execution_count": 139,
      "outputs": [
        {
          "execution_count": 139,
          "output_type": "execute_result",
          "data": {
            "text/plain": "array([[ 1.66666667,  1.66666667],\n       [ 1.66666667,  1.66666667]])"
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      "cell_type": "code",
      "source": "np.corrcoef(da_vals[0,0,:] , dm_vals)",
      "execution_count": 123,
      "outputs": [
        {
          "execution_count": 123,
          "output_type": "execute_result",
          "data": {
            "text/plain": "array([[ 1.,  1.],\n       [ 1.,  1.]])"
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      "cell_type": "code",
      "source": "def normalize(da, dim):\n    da_norm = da- da.mean(dim)\n    da_norm = da_norm/da.std(dim)\n    return da_norm",
      "execution_count": 151,
      "outputs": []
    },
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      "cell_type": "code",
      "source": "dim = 't'\ncor = normalize(da, dim).dot(normalize(dm, dim))/(da[dim].shape[0])#/(da.std(dim)*dm.std(dim))\ncor",
      "execution_count": 174,
      "outputs": [
        {
          "execution_count": 174,
          "output_type": "execute_result",
          "data": {
            "text/plain": "<xarray.DataArray (x: 6, y: 5, z: 4)>\narray([[[ 1.,  1.,  1.,  1.],\n        [ 1.,  1.,  1.,  1.],\n        [ 1.,  1.,  1.,  1.],\n        [ 1.,  1.,  1.,  1.],\n        [ 1.,  1.,  1.,  1.]],\n\n       [[ 1.,  1.,  1.,  1.],\n        [ 1.,  1.,  1.,  1.],\n        [ 1.,  1.,  1.,  1.],\n        [ 1.,  1.,  1.,  1.],\n        [ 1.,  1.,  1.,  1.]],\n\n       [[ 1.,  1.,  1.,  1.],\n        [ 1.,  1.,  1.,  1.],\n        [ 1.,  1.,  1.,  1.],\n        [ 1.,  1.,  1.,  1.],\n        [ 1.,  1.,  1.,  1.]],\n\n       [[ 1.,  1.,  1.,  1.],\n        [ 1.,  1.,  1.,  1.],\n        [ 1.,  1.,  1.,  1.],\n        [ 1.,  1.,  1.,  1.],\n        [ 1.,  1.,  1.,  1.]],\n\n       [[ 1.,  1.,  1.,  1.],\n        [ 1.,  1.,  1.,  1.],\n        [ 1.,  1.,  1.,  1.],\n        [ 1.,  1.,  1.,  1.],\n        [ 1.,  1.,  1.,  1.]],\n\n       [[ 1.,  1.,  1.,  1.],\n        [ 1.,  1.,  1.,  1.],\n        [ 1.,  1.,  1.,  1.],\n        [ 1.,  1.,  1.,  1.],\n        [ 1.,  1.,  1.,  1.]]])\nDimensions without coordinates: x, y, z"
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        "description": "Testing the possibility of xarray dot product of two DataArrays along their shared dims.",
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