Find x and y on arch-CodePudding

Hello all. I'm not very good with math, so I will need help writing a function in Python. There is an arch and I need to know the x and y of each pixel on the arch. All the data that I have, I have written in the picture. Let me know if anything needs to be clarified further.

CodePudding user response：

Having arc length and radius, we can find arc angle in radians

fi = L/R= 366.5/350  (60 degrees, BTW)

Half-angle

hf = fi/2 = 366.5/700   (30 degrees)

Circle center coordinates

cx = R * sin(hf) = 350*1/2 = 175
cy = R * cos(hf) = 350*0.866 = 303.1

Now we can make loop to get pixel coordinates with given resolution with starting angle -Pi/2-Pi/6 (in general case -Pi/2-hf)

for i in range(2220):
   an = -math.pi*2/3     i * 366.5/350 / 2220
   x = cx   R * math.cos(an)
   y = cy   R * math.sin(an)

To correct your code:

cx = radius * math.sin(hf)
cy = -radius * math.cos(hf)

xl.append(cx   radius * math.cos(an))
yl.append(cy - radius * math.sin(an))