@@ -1095,22 +1095,18 @@ P1 = np.random.uniform(-10,10,(10,2))
10951095p = np.random.uniform(-10,10,( 1,2))
10961096
10971097def distance_faster(P0,P1,p):
1098- '''
1099- Author: Hemanth Pasupuleti
1100- Reference: https://mathworld.wolfram.com/Point-LineDistance2-Dimensional.html
1101-
1102- ---- Explainable solution - Slightly Faster as number of lines scale up exponentially ----
1103- '''
1104- v = P1- P0 # Shape: (n_lines,2), Compute: [(x2-x1) (y2-y1)]
1105- v[:,[0,1]] = v[:,[1,0]] # Shape: (n_lines,2), Swap along axis to Compute: [(y2-y1) (x2-x1)]
1106- v[:,1]*=-1 # Shape: (n_lines,2), Compute: [(y2-y1) -(x2-x1)]
1107- norm = np.linalg.norm(v,axis=1) # Shape: (n_lines,), Compute: sqrt((x2-x1)**2 + (y2-y1)**2)
1108- r = P0 - p # Shape: (n_lines,2), Compute: [(x1-x0) (y1-y0)]
1109-
1110- # np.einsum('ij,ij->i',r,v) is equivalent to np.multiply(r,v)).sum(axis=1) which is scalar product of two matrices across axis 1.
1111-
1112- d = np.abs(np.einsum("ij,ij->i",r,v)) / norm # Shape: (n_lines,), Compute: d = |(x1-x0)*(y2-y1)-(y1-y0)*(x1-x0)|/sqrt((x2-x1)**2 + (y2-y1)**2)
1098+ #Author: Hemanth Pasupuleti
1099+ #Reference: https://mathworld.wolfram.com/Point-LineDistance2-Dimensional.html
1100+
1101+ v = P1- P0
1102+ v[:,[0,1]] = v[:,[1,0]]
1103+ v[:,1]*=-1
1104+ norm = np.linalg.norm(v,axis=1)
1105+ r = P0 - p
1106+ d = np.abs(np.einsum("ij,ij->i",r,v)) / norm
1107+
11131108 return d
1109+
11141110print(distance_faster(P0, P1, p))
11151111
11161112##--------------- OR ---------------##
@@ -1121,6 +1117,7 @@ def distance_slower(P0, P1, p):
11211117 U = U.reshape(len(U),1)
11221118 D = P0 + U*T - p
11231119 return np.sqrt((D**2).sum(axis=1))
1120+
11241121print(distance_slower(P0, P1, p))
11251122
11261123< q79
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