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Carto Rep for watershed subbasin boundary

November 07 2011 | 6 comments
Categories: Symbology

Hi,

I am trying to create a line carto rep for watershed subbasins. I have looked at the Desktop Help and done web searches.....to no avail. Maybe it is the prescription drugs (I had surgery last week) or the non-prescription drugs (I was a child of the 60's) but I can't get my head around the instructions. Could you please explain the process as if I was a 4th grader.

The symbol is part of the "FGDC Digital Cartographic Standard for Geologic Map Symbolization". The reference number is 26.7.2.

Thank you

Mapping Center Answer:

Start by making the line symbol. Click Customize on the top bar menu then Style Manager to Open Style Manager. In your style (or another in which you have write capability) click the Line Symbols folder in the left panel. In the right panel, right click, click New > Line Symbol. In the Symbol Property Editor, change the Type to Cartographic Line Symbol. Here are the specs for the line symbol:

  • Lineweight .425 mm
  • Dash length 5.0 mm
  • Dot diameter .45mm
  • Spacing .5mm

Click OK to keep your changes and rename the symbol to 26_7_2 (or whatever you want).

Next apply the symbol to your features. In the table of contents, right click the feature class that you want to apply the symbol to adn click Properties. On the Symbology tab, use the Features – Single Symbol renderer and click the symbol patch. Select the line symbol that you created to apply it to the features in the feature class. Click OK. If there are no connections among the lines (intersections), you can stop here. You only really need to use carto reps if you want cleaner intersections since this happens to be a dashed line symbol.

Next convert the feature class to representations – note that your data need to be in a geodatabase in order to perform this next step. Right click the symbolized layer in the table of contents and click Convert Symbology to Representation. Zoom in to see some of the intersections. Are they to your liking? If not, then you may need to adjust the properties of the cartographic representations line symbol. To do this, right click the layer in the table of contents, click Properties and on the Symbology tab, modify the settings for the Dashes. You can also add additional control points to set how the lines join at sharper angles (in addition to the intersections).

Here is the online help topic that describes the Dashes and Add control points settings: List of representation geometric effects

Names of symbols in a style posted by Aileen Buckley on Nov 7 2011 8:04PM
Note that I said you could call the style whatever you want, but that is not strictly true -- you cannot use special characters in the style name (like a period, which is why I used underscores).
A better class of 4th graders posted by Chris Pratt on Nov 7 2011 9:23PM
You must deal with very sharp 4th graders.

How are you establishing a dash length of 5.0mm in the symbol property editor? Because in mine, the interval and line pattern is calculated in points. And where and how are you setting a dot diameter? The symbol calls for dots, not square dashes.
Unit conversion posted by Aileen Buckley on Nov 8 2011 3:10PM
Well, one millimeter equals 0.03937 inches, and there are 72 points in an inch so you would multiply any values in millimeters by 2.83464 (i.e., 0.03937 * 72) to get the millimeter values in points. So, 0.425 mm equals about 1.2 points, 5.0 mm equals about 14.2 points and 0.45 mm equals about 1.28 points, and 0.5 mm equals about 1.32 points.
Rounded ends on dashes and round dots posted by Aileen Buckley on Nov 8 2011 4:26PM
Note that if you want the dots to be round in the dashed lined symbol, you can set the Line Caps property (on the Cartographic Line tab of the Symbol Property Editor) to Round. This will also make the ends of the line symbol round. If you want the dots to be round but no the dashes, then make this a 2 layer symbol, using the template for each layer to properly place the dashes relative to the dots. Then you can set the dot layer to have round line caps and the dash layer to have square or butt line caps.

A third option is to make the dot layer of the symbol a Marker Line Symbol and use a solid circle for the dot. Make the circle size the same as the line width, and use the template to place the dot correctly relative to the dashes.
Unit Conversion Reply posted by Chris Pratt on Nov 8 2011 4:37PM
Aileen,

Thank you for your prompt reply. That answers the measurement question.

Now let's get to the dots. Correct me if I am wrong, but creating a cartographic line will not create dots. It will simply create small squares. The symbology calls for two round dots so small squares do not work.
Correct - use third option posted by Aileen Buckley on Nov 8 2011 4:42PM
You are correct -- that is why we included the third option.

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