Included hex to RGB conversion in rgb_sweep

docs/source/api.rst

@@ -10,7 +10,9 @@ Parallel Utilities
 
 Plot Utilities
 ==============
-.. automodule:: skued.plot_utils
+.. autofunction:: skued.plot_utils.spectrum_colors
+
+.. autofunction:: skued.plot_utils.rgb_sweep
 
 Array Utilities
 ===============

skued/plot_utils.py

@@ -6,7 +6,7 @@
 from collections import Iterable
 from colorsys import hsv_to_rgb
 
-def linspace(start, stop, num):
+def _linspace(start, stop, num):
 	""" 
 	Generate linear space 
 
@@ -23,12 +23,29 @@ def linspace(start, stop, num):
 	------
 	val : float
 	"""
-	step = (stop - start)/num
+	# Since we always include the endpoint,
+	# step does not count the last yield
+	step = (stop - start)/(num - 1)
 
 	val = start
-	for _ in range(num):
+	for _ in range(num - 1):
 		yield val
 		val += step
+	yield stop
+
+def _hex_to_rgb(value):
+	""" Return an RGB tuple (float 0 to 1) from an hexadecimal 
+	string representation. """
+	value = value.lstrip('#')
+	char_per_color = len(value) // 3
+
+	red = int(value[0:char_per_color], base = 16)
+	green = int(value[char_per_color:2*char_per_color], base = 16)
+	blue = int(value[2*char_per_color::], base = 16) 
+
+	# We want color values between 0.0 and 1.0
+	max_bits = 16**char_per_color - 1
+	return (red/max_bits, green/max_bits, blue/max_bits)
 
 def spectrum_colors(num_colors):
 	"""
@@ -70,21 +87,29 @@ def rgb_sweep(num_colors, source, dest):
 	----------
 	num_colors : int
 		Number of colors to generate.
-	source : 3-tuple of floats
+	source : 3-tuple of floats or str
 		Source color in RGB space. Values should be between 0.0 and 1.0.
-	dest : 3-tuple of floats
-		Destination color in RGB space. Values should be between 0.0 and 1.0.
+		if `source` is a string, it is assumed to be in hexadecimal representation.
+	dest : 3-tuple of floats or str
+		Destination color in RGB space. RGB tuple Values should be between 0.0 and 1.0.
+		If `dest` is a string, it is assumed to be in hexadecimal representation.
 	
 	Yields
 	------
 	color : (R,G,B) tuple.
 		R, G, B values in a tuple, from 0.0 to 1.0.
 	"""	
+	if isinstance(source, str):
+		source = _hex_to_rgb(source)
+
+	if isinstance(dest, str):
+		dest = _hex_to_rgb(dest)
+
 	red_src, grn_src, blu_src = source
 	red_dst, grn_dst, blu_dst = dest
 
-	reds = linspace(red_src, red_dst, num = num_colors)
-	greens = linspace(grn_src, grn_dst, num = num_colors)
-	blues = linspace(blu_src, blu_dst, num = num_colors)
+	reds = _linspace(red_src, red_dst, num = num_colors)
+	greens = _linspace(grn_src, grn_dst, num = num_colors)
+	blues = _linspace(blu_src, blu_dst, num = num_colors)
 
 	yield from zip(reds, greens, blues)

skued/tests/test_plot_utils.py

@@ -35,6 +35,13 @@ def test_source_equal_to_dest(self):
 		""" Test that rgb_sweep still works if source is equal to destination."""
 		colors = rgb_sweep(10, source = (1,0,0), dest = (1,0,0))
 		self.assertEqual(len(list(colors)), 10)
+
+	def test_hex_colors(self):
+		""" Test that rgb_sweep works on hexadecimal strings """
+		colors = list(rgb_sweep(10, source = '#ffffff', dest = '#000000'))
+
+		self.assertSequenceEqual(colors[0], (1.0, 1.0, 1.0))
+		self.assertSequenceEqual(colors[-1], (0.0, 0.0, 0.0))
 
 if __name__ == '__main__':
 	unittest.main()