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Can anyone please explain what is wrong with this equation?


New member
Can anyone please explain what is wrong with this equation:




im using it in spherical coordinates, i keep trying to alter the equation about to get it to work, but keep failing!! Sometimes it fails due to the 'sin' comment

please explain


New member
try this set.....

rho = .8 + 1.6 * sin(6 *theta)

theta = 360 * t

phi = 0.6 * sin(12 *theta)

is this the shape you're looking for?


New member
i forgot an explanation.... your range is way too small. you are setting to be from 0 to 2. do you happen to have a picture of what you want it to look like?

you can just use this one also....

rho = 0.8 + 1.6 *sin(6*t* 300)

theta = 2* t * 300

phi = 0.6 * pi * sin(12*t*300)


New member

Not long ago I tried modeling a sinusoidal cooling fin using the SIN(x) function. As mathematics hoes, I at first assumed that the argument x had to be in radians. I tried and tried and couldn't get it to work. Finally, I tried converting the argument x to degrees ala (180x/pi). It worked!