Symbolising options for ArcGIS Online?

Symbolizing Options for ArcGIS Online: Making Your Maps Pop

Let’s face it, raw data on a map can be, well, a little boring. But ArcGIS Online gives you a ton of ways to spice things up, turning those dry numbers into visuals that really tell a story. Whether you’re a GIS whiz or just starting out, understanding how to use symbols effectively is key to making maps that people actually want to look at. So, let’s dive into the world of symbology in ArcGIS Online, from the super-smart “Smart Mapping” to getting down and dirty with custom symbols.

Smart Mapping: Your Cartographic Co-Pilot

Imagine having a cartographer sitting next to you, whispering suggestions as you build your map. That’s kind of what Smart Mapping in ArcGIS Online feels like. Since its debut back in 2015, this feature has been a game-changer. Instead of staring at a blank screen, wondering where to even begin, Smart Mapping analyzes your data and suggests styles, color schemes, and symbols that make sense i. It’s like having a built-in design assistant!

I remember the first time I used Smart Mapping. I was mapping housing prices in my city, and honestly, I was overwhelmed. But then Smart Mapping suggested using different shades of green to represent price ranges. Suddenly, the map came alive, showing me clear patterns I hadn’t noticed before.

Smart Mapping is especially handy because it suggests the best visualization techniques based on your data type. Mapping population density? It might recommend a “Counts and Amounts” style, where darker colors represent higher densities. Mapping different types of businesses? It’ll probably suggest unique symbols for each category. It really takes the guesswork out of map design.

Symbol Types: A World of Possibilities

ArcGIS Online offers a whole bunch of symbol types to represent your data, whether it’s points, lines, or polygons. Think of it as your cartographic toolbox, filled with different instruments for different jobs.

• Single Symbol: Sometimes, simplicity is key. Use the same symbol for everything in a layer to highlight locations or show a basic distribution. Think of it like marking all the parks in a city with a simple green dot.
• Unique Symbols: Got categories? This style is your friend. Assign a different symbol to each category based on an attribute field. Perfect for showing different types of land use, for example.
• Counts and Amounts: This is where you visualize the numbers. Use varying symbol sizes or colors to represent numerical data. This is the go-to for showing population, income, or any other quantitative data. You’ve got options here:
  • Color: Use a color ramp to represent data ranges. Darker shades usually mean higher values, but you can flip it if you want!
  • Size: Scale the symbol size to the data value. Bigger circles mean bigger numbers. Simple as that.
• Heat Maps: Want to show density? Heat maps are your answer. They display the concentration of point features as a smooth, colorful surface. Think of it like showing where all the coffee shops are clustered in a city.

But wait, there’s more! You can customize pretty much every aspect of your symbols: color, size, shape, transparency… you name it. You can even upload your own custom symbols. Have a specific logo you want to use? Go for it! Just make sure they’re in PNG, GIF, JPG, or SVG format. Vector symbols are great because they scale without getting pixelated.

Attribute-Driven Symbology: Taking It to the Next Level

Ready to get really fancy? Attribute-driven symbology lets you connect symbol properties directly to your data. This means your symbols can change dynamically based on the underlying attributes. It’s like your map is alive, responding to the data in real-time.

With attribute-driven symbology, you can customize symbols to reflect different aspects of the data by connecting rendering properties to feature attributes i. These feature attributes can include normal attributes in your data, as well as Arcade functions i.

Here’s the deal:

• Connect the Dots (or Colors, or Sizes): Link symbol properties like color, size, rotation, and transparency to attribute fields or Arcade expressions.
• Arcade Magic: Arcade is a scripting language built into ArcGIS that lets you do all sorts of cool things. Use it to combine multiple attributes into a single color code or calculate a size based on a complex formula. The possibilities are endless!
• Color Definitions: When you’re messing with color, you need to provide a string field or an Arcade expression that spits out a string. This string has to follow the rules of CSS Color Module Level 3 or any color model that ArcGIS Pro supports.

A Few Pointers to Keep in Mind

• Symbol Size: Keep your custom symbols under 120×120 pixels. Nobody wants a map cluttered with giant icons.
• File Format: PNGs with transparent backgrounds or SVGs are your best bet.
• Performance: Too many unique custom symbols can slow things down. Keep it reasonable.
• Web Styles: Want to keep your symbols consistent across your organization? Publish web styles from ArcGIS Pro and use them in Map Viewer.
• Transparency: If your symbol doesn’t fill the square, use a PNG or GIF with a transparent background to avoid ugly white borders.

Mastering symbology in ArcGIS Online is like learning to speak a new language. Once you get the hang of it, you can create maps that are not only beautiful but also incredibly effective at communicating information. So, play around with the options, experiment with different styles, and don’t be afraid to get creative. Your maps will thank you for it!