8 Replies Latest reply on May 27, 2013 12:51 PM by pixelthunder

# Circular chart

Hi guys,

Please don't shoot me down in flames, I've only been using Illustrator for about a month, so please excuse me if my question is one worthy of mockery.

Basically I want to create a circular chart consisting of an outer quarter-circle, split up into say 40 small rectangles. Then another quarter circle, closer to the centre of the circle, split up into a smaller number of rectangles, but keeping the spaces between the rectangles inline with the spaces of the first quarter circle. I've tried creating a pattern, drawing a circle etc, replacing the spine after doing a blend, but I think I must be missing something because I can't get it quiet right.  If I do rotate 360/x, it works fine for first row, but then when I get closer, even if I reduce the number I'm dividing 360 by, it just doesn't line up perfectly and gets worse as I get close to the centre.

Cris

• ###### 1. Re: Circular chart

Cris,

I am afraid you will have to present what you have made already, with the first two rows. If you cannot get the Insert Image (the camera icon in the message box) to work, you may upload an image to own/free site and post a link.

Or you may try to go deeper into explaining the quarter circle where rectangles fit in (seemingly with a distance), or the exact way to combine a pattern and a blend with a replaced spine.

There are different ways to get rectangles (or derived shapes) rotated and distributed round (part of) a circle, and the best/easiest one depends on the specific conditions/properties.

• ###### 2. Re: Circular chart

Nothing to do with AI or your inexperince in using it. Simple school grade math:

Circumference = diameter * Pi

When you have a 10mmx10mm rectangle and want 3mm space between it, in reverse this means:

(10mm+3mm)*40/Pi = ~165mm

Now inset the next row by 10+3mm:

(165-13)*Pi = ~477mm

477/13 = ~36

You can now already only place 36 rectangles. The smaller your circles get, the less will fit. Based on what you have dreamed up and what values you use, it will never be possibe to get an even distribution on all circles. Again, you simply have your math wrong.

Mylenium

• ###### 3. Re: Circular chart

Thank you both for your reply. Mylenium, thank you very much for the explanation. I assumed there was a mathematical solution to my problem, I didn't want to make the suggestion in case I was miles off.

What a really friendly forum!

Thank you both again for your replies!

• ###### 4. Re: Circular chart

For my small part you are welcome, Cris.

Just a small addition: Obviously, rectangles distributed round a circle will have a greater distance at the outer ends and shorter at the inner ends. If you wish a maximum/average/minimum distance, the circle should correspond to the outer end/middle/inner end of the rectangles.

Luckily, there are many eyes that often read differently.

• ###### 5. Re: Circular chart

I want...40 small rectangles. Then another quarter circle...a smaller number of rectangles...keeping the spaces...inline....

Keeping the spaces radially in line, of course, means that each of the "smaller number" will have to be a multiple of the individual rectangles in the outer ring.

Also, actual rectangles arranged around an arc are going result in wedge-shaped spaces between them. That may be what you want; but it sounds like you simply want a radial array.

Polar Grid Tool: Click (don't drag). Enter the desired values in the resulting dialog.

Pathfinder palette: Click the Divide button. This splits/joins the open radial paths and the closed circular paths of the grid into closed cells.

White Pointer: Drag a marquee selection around half of the array.

Delete twice, so you don't leave stray points resulting from partially selected paths.

Similarly marquee select and delete half of the remaining paths.

Lasso Tool: Drag a marquee selection around the unwanted rows and similarly delete them.

Apply white stroke and desired fill color.

LivePaint (flood fill/stroke) Tool: Change current fill color. Click every-other cell of the outer ring.

LivePaint Tool: Similarly color the inner ring, but this time, drag across two (or as many as desired) adjacent cells.

Set current stroke to None.

LivePaint Tool: click the unwanted dividers.

Now you'll probably come back and say you need text in each of those boxes. This kind of radial graph has been discussed here several times. You can probably find the discussions by doing a search.

JET

• ###### 6. Re: Circular chart

Thanks for the suggestions guys, this is an example of the kind of feel I'm going for.... I've contacted the guy (or attempted to) thats actually made this, but he hasnt got back to me. Hence me coming here for some help

• ###### 7. Re: Circular chart

Cris,

What about using a Pattern Brush with a suitable shape (rectangle or rounded distance) and a suitable distance (10%/20%/whatever?

You could also use a simple Stroke with Dashed Line (small gaps) which may adapt to the length depending on version; up to CS5 you may use the free Adjust Dashes script available here:

http://park12.wakwak.com/~shp/lc/et/en_aics_script.html