I'm trying to figure how to make a circle split in half with the top half black and the bottom white. I've made a circle with a 37 pt black stroke, now I just need to make half of it white. Or I may be going about it wrong. Seems like it ought to be simple.
Start by drawing the circle. Then draw a straight, horizontal path extending beyond the circle in both directiolns. Select both and use the Align panel to center the two both horizontally and vertically. De-select the circle and then use Object>Path>Divide Objects Below. Select each half and apply the desired color.
By far the easiest way is to make two identical circles.
Using the Direct Selection tool, delete the right-hand anchor of one of them and the left-hand anchor of the other.
Colour the resulting two half circles as you will and snap them together.
You can do this with Gradients on Strokes.
Set the stroke to have a white to black gradient (the default gradient)
Click the white gradient stop and enter 50 in the Location field. Click the black gradient stop and enter 50 in the location field.
Change the angle field to whatever you want. 90° in my image so top is black bottom is white.
Grey circle added behind so the white can be seen here.
You really should mark Scott's posting as the answer this is such a clever way of doing such a thing and a real time saver that it would really help others to see the technique Scott used.
I ask you to please mark Post #7 as the anwer.
I really like the way Scott suggests.
However, I believe, as always, that there are always different ways of doing things, each in its own right. Each way may serve some purposes better than others (in both senses).
If we look at simplicity/efficiency, and just compare the (count of) steps that differ between the suggestions in posts #1 and 7.
For a first use, #1 requires 2 cllicks with the Scissors Tool and 1 setting of each colour to change, whereas #7 requires 3 settings of gradient stop positions and 2 settings of colour (4 for other colours than black and white).
For a subsequent use, #1 requires 1 setting of each colour to change, whereas #7 requires 2 settings of gradient stop positions and 2 settings of each colour to change.
It should be noted that neither #1 nor #7 imply any fill.
The number of clicks and settings does knot necessarily means faster or slower and if you consider that Scots method gives one object aa opposed to two ly one stroke instead of two. It might in the long run save time and effort.
It seems that everything said here confirms the equality of different solutions.
And grouping is easy, making paths operable together.
I also like the solutions presented by Steve and Emil. And the one by Larry was quite obvious for the other possible interpretation of the OP.
If I had to choose a favourite in this case, it might be the one by Emil, as I understand it (rather than how I read it), namely to create the circle, copy it to the front, delete the top (or bottom) Anchor Point, and change the colour of the still selected halved circle, then group.
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