flexibility to return with alpha channel and/or as string

This commit is contained in:
Eureka Pai 2021-12-10 12:52:44 -05:00
parent 7bb6707b0e
commit 2b6283bbe3
2 changed files with 40 additions and 15 deletions

View File

@ -193,25 +193,39 @@ class Colormap(mpl.colors.ListedColormap):
def at(self,
fraction : float) -> np.ndarray:
fraction : Union[float,Sequence[float]],
with_alpha : bool = False,
as_string : bool = False) -> np.ndarray:
"""
Interpolate color at fraction.
Parameters
----------
fraction : float
Fractional coordinate to evaluate Colormap at.
fraction : float or sequence of float
Fractional coordinate(s) to evaluate Colormap at.
with_alpha : bool
Provide opacity as fourth value.
as_string : bool
Encode color as 'rgb(r,g,b)' or 'rgba(r,g,b,a)'.
Returns
-------
color : np.ndarray, shape(3)
RGB values of interpolated color.
color : np.ndarray, shape(3 or 4), or string
RGB(A) values of interpolated color.
"""
return interp.interp1d(np.linspace(0,1,self.N),
def _stringify(color):
d = color.shape[-1]
c = np.array([f'rgba({c[0]},{c[1]},{c[2]},{c[3]})' if d==4
else f'rgb({c[0]},{c[1]},{c[2]})' for c in np.atleast_2d(color)])
return c if len(c)>1 else c[0]
color = interp.interp1d(np.linspace(0,1,self.N),
self.colors,
axis=0,
assume_sorted=True)(fraction)
assume_sorted=True)(fraction)[...,:4 if with_alpha else 3]
return _stringify(color) if as_string else color
def shade(self,

View File

@ -139,12 +139,23 @@ class TestColormap:
c += c
assert (np.allclose(c.colors[:len(c.colors)//2],c.colors[len(c.colors)//2:]))
@pytest.mark.parametrize('N,cmap',[
(8,'gray'),
(17,'gray'),
@pytest.mark.parametrize('N,cmap,at,with_alpha,result',[
(8,'gray',0.5,False,[0.5,0.5,0.5]),
(17,'gray',0.5,False,[0.5,0.5,0.5]),
(17,'gray',[0.5,0.75],False,[[0.5,0.5,0.5],[0.75,0.75,0.75]]),
])
def test_at(self, N, cmap):
assert np.allclose(Colormap.from_predefined(cmap,N=N).at(0.5)[:3],0.5,rtol=0.005)
def test_at_value(self, N, cmap, at, with_alpha, result):
assert np.allclose(Colormap.from_predefined(cmap,N=N).at(at,with_alpha=with_alpha),
result,
rtol=0.005)
@pytest.mark.parametrize('N,cmap,at,with_alpha,result',[
(8,'gray',0.5,False,'rgb(0.5,0.5,0.5)'),
(8,'gray',0.5,True,'rgba(0.5,0.5,0.5,1.0)'),
(8,'gray',[0.5,0.25],True,['rgba(0.5,0.5,0.5,1.0)','rgba(0.25,0.25,0.25,1.0)']),
])
def test_at_string(self, N, cmap, at, with_alpha, result):
assert np.all(Colormap.from_predefined(cmap,N=N).at(at,with_alpha=with_alpha,as_string=True) == result)
@pytest.mark.parametrize('bounds',[None,[2,10]])
def test_shade(self,ref_path,update,bounds):