# Grasshopper Help

Grasshopper Arc.

I am wanting to draw an arc, I can set the centre, I can set the radius, But the A eludes me as to what it wants!

Help tells you that this is where you give the Angle, and yes I have tried, all kinds of options.

Anyway.

What I need is an answer so an idiot can understand.

Let’s say I want to draw a quadrant arc, from the right side, ( X ) swinging anticlockwise, to stop at 90 degrees from the start. What do I need to input into A?

0 to Pi, 20 to Pi, 180 to Pi, 90 to 0. What ever I enter it draws the arc, but with no logic as to why and where from and too. I am lost. Yes I can draw an arc, but with no control as to its start and stop location. It is a lottery, and I haven’t won.

Is there a good idiots guide, that instead of telling you that is the point to plug your data in. It actually tells you, and shows you an example of the data required and its format. ( not some high brow nonsense term only Albert would understand )

But the A eludes me as to what it wants!

Angle = rotation in radians. You can change it to degrees by right clicking the A input and set to degrees or use degree to radians component.

but with no logic as to why and where from and too

The logic is you are creating an arc around a center point by a radius and from 0 to A.

Yes I can draw an arc, but with no control as to its start and stop location.

Have you tried the Arc3Pt component?

Use Degree to Radians component , domain from (0 - 360) of course

I understand the process, but not the input! And yes I have tried theArc3Pt. It too has me beat.

Drawing an arc from 3 o’clock to 6 o’clock, 90 degrees.

I have the centre point, I have the radius, but what to put into A ?

To define the start point of the arc, and the finish point.