prevent numpy ComplexWarnings

proxtoolbox/Utilities/OrbitalTomog/interpolation.py

@@ -3,6 +3,7 @@ from .array_tools import shifted_fft, shifted_ifft, roll_to_pos
 
 __all__ = ['fourier_interpolate']
 
+
 def fourier_interpolate(arr: np.ndarray, factor: any = 2., **kwargs) -> np.ndarray:
     """
     Interpolation by padding in the Fourier domain.
@@ -30,7 +31,10 @@ def fourier_interpolate(arr: np.ndarray, factor: any = 2., **kwargs) -> np.ndarr
             out = fourier_interpolate_3d(arr, factor=factor, **kwargs)
         else:
             raise NotImplementedError('Can only interpolate 2d or 3d arrays as of now')
-    return out.astype(arr.dtype, casting='unsafe')
+    if np.isrealobj(arr):
+        return out.real.astype(arr.dtype, casting='unsafe')
+    else:
+        return out.astype(arr.dtype, casting='unsafe')
 
 
 def fourier_interpolate_2d_nonsquare(arr: np.ndarray, factor: tuple = (1., 2.),