Fix doc string of warp functions

skimage/transform/_geometric.py

@@ -962,8 +962,13 @@ def warp(image, inverse_map=None, map_args={}, output_shape=None, order=1,
         Shape of the output image generated. By default the shape of the input
         image is preserved.
     order : int, optional
-        The order of the spline interpolation, default is 3. The order has to
-        be in the range 0-5.
+        The order of interpolation. The order has to be in the range 0-5:
+        * 0: Nearest-neighbor
+        * 1: Bi-linear (default)
+        * 2: Bi-quadratic
+        * 3: Bi-cubic
+        * 4: Bi-quartic
+        * 5: Bi-quintic
     mode : string, optional
         Points outside the boundaries of the input are filled according
         to the given mode ('constant', 'nearest', 'reflect' or 'wrap').

skimage/transform/_warps_cy.pyx

@@ -40,22 +40,18 @@ def _warp_fast(cnp.ndarray image, cnp.ndarray H, output_shape=None,
     """Projective transformation (homography).
 
     Perform a projective transformation (homography) of a
-    floating point image, using bi-linear interpolation.
+    floating point image, using interpolation.
 
     For each pixel, given its homogeneous coordinate :math:`\mathbf{x}
     = [x, y, 1]^T`, its target position is calculated by multiplying
     with the given matrix, :math:`H`, to give :math:`H \mathbf{x}`.
-    E.g., to rotate by theta degrees clockwise, the matrix should be
-
-    ::
+    E.g., to rotate by theta degrees clockwise, the matrix should be::
 
       [[cos(theta) -sin(theta) 0]
        [sin(theta)  cos(theta) 0]
        [0            0         1]]
 
-    or, to translate x by 10 and y by 20,
-
-    ::
+    or, to translate x by 10 and y by 20::
 
       [[1 0 10]
        [0 1 20]
@@ -69,12 +65,12 @@ def _warp_fast(cnp.ndarray image, cnp.ndarray H, output_shape=None,
         Transformation matrix H that defines the homography.
     output_shape : tuple (rows, cols), optional
         Shape of the output image generated (default None).
-    order : {0, 1}, optional
+    order : {0, 1, 2, 3}, optional
         Order of interpolation::
-        * 0: Nearest-neighbour interpolation.
-        * 1: Bilinear interpolation (default).
-        * 2: Biquadratic interpolation.
-        * 3: Bicubic interpolation.
+        * 0: Nearest-neighbor
+        * 1: Bi-linear (default)
+        * 2: Bi-quadratic
+        * 3: Bi-cubic
     mode : {'constant', 'reflect', 'wrap', 'nearest'}, optional
         How to handle values outside the image borders (default is constant).
     cval : string, optional (default 0)