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Managing color ramps using style manager (or using styles to transfer only color symbology)...

February 28 2008 | 0 comments
Categories: Symbology

I am creating a series of 30-odd maps showing routes on a street network and am using a specific color palette of eight colors to symbolize the routes, of which there can be up to 40 per map, with unique IDs and I'd like to find a convenient way to manage my color palette.

I created a custom color ramp using the Style Manager tool, but find that when I use this ramp, the routes are assigned colors in a seemingly random pattern, rather than the strict order in which I placed the colors in the ramp. I used 8 preset color ramps to make a multipart ramp which would always have more color values than the routes I might be reuqired to map (as I found if I had fewer colors on the ramp than routes, the ramp would be 'evenly' distributed among the routes, e.g., the first three routes would have the first color, then the next three routes would have the second color and so on, with all colors evenly represented but adjacently numbered routes having the same color).

I found that if I had more colors than routes then they would not necessarily be 'evenly' distributed in this way. However, the distribution seems to be random, rather than preserving the sequence of colors as I created them in the color ramp.

I would like to be able to do either one of two things: always have the first route start with the first color in the ramp and proceed sequentially, or set the colors as necessary (manually) and then import the color scheme to a new feature class, without changing all the other symbology properties of that second feature class (e.g., being able to globally set all routes in feature class 2 to be offset and a different width than the first feature class, but then bring in the colors established in the first feature class).

It seems like the style manager must have some way of dealing with this (besides creating a specific style for each route, of which there will be hundreds eventually) but I can't seem to figure it out. Any suggestions? Thanks!

Mapping Center Answer:

It sounds like you want to be able to apply a color ramp to a specific set of routes. To do that you would make a separate color ramp for each of the eight your eight colors (these would be the ramps that make up your multipart ramp.

Then to symbolize, you have a couple options. First you could make a layer for each of the eight colors, using a definition query to separate the features. Then use the appropriate color ramp on each layer.

Second, you can use the unique values symbology method and take advantage adding headings (in the symbology tab of the layer properties dialog, you can select a row in the list of unique values, right-click, and choose move to heading. (we did a blog entry explaining how to do this in a bit more detail called "Organizing layers with too many unique values" You can assign your color ramps to each header, allowing everything to be shown with one layer.

Once you get the proper colors assigned to the features, convert the the symbology to representations, which will store the symbols with the data and then you can use those symbols on your other maps. Note you will need 9.2 to do that along with having your data stored in a geodatabase.

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