HEAVY.AI Docs
v7.2.4
v7.2.4
  • Welcome to HEAVY.AI Documentation
  • Overview
    • Overview
    • Release Notes
  • Installation and Configuration
    • System Requirements
      • Hardware Reference
      • Software Requirements
    • Installation
      • Free Version
      • Installing on CentOS
        • HEAVY.AI Installation on CentOS/RHEL
        • Install NVIDIA Drivers and Vulkan on CentOS/RHEL
      • Installing on Ubuntu
        • HEAVY.AI Installation on Ubuntu
        • Install NVIDIA Drivers and Vulkan on Ubuntu
      • Installing on Docker
        • HEAVY.AI Installation using Docker on Ubuntu
      • Getting Started on AWS
      • Getting Started on GCP
      • Getting Started on Azure
      • Getting Started on Kubernetes (BETA)
      • Upgrading
        • Upgrading HEAVY.AI
        • Upgrading from Omnisci to HEAVY.AI 6.0
        • CUDA Compatibility Drivers
      • Uninstalling
      • Ports
    • Services and Utilities
      • Using Services
      • Using Utilities
    • Executor Resource Manager
    • Configuration Parameters
      • Overview
      • Configuration Parameters for HeavyDB
      • Configuration Parameters for HEAVY.AI Web Server
    • Security
      • Roles and Privileges
      • Connecting Using SAML
      • Implementing a Secure Binary Interface
      • Encrypted Credentials in Custom Applications
      • LDAP Integration
    • Distributed Configuration
  • Loading and Exporting Data
    • Supported Data Sources
      • Kafka
      • Using Heavy Immerse Data Manager
      • Importing Geospatial Data
    • Command Line
      • Loading Data with SQL
      • Exporting Data
  • SQL
    • Data Definition (DDL)
      • Datatypes
      • Users and Databases
      • Tables
      • System Tables
      • Views
      • Policies
    • Data Manipulation (DML)
      • SQL Capabilities
        • ALTER SESSION SET
        • ALTER SYSTEM CLEAR
        • DELETE
        • EXPLAIN
        • INSERT
        • KILL QUERY
        • LIKELY/UNLIKELY
        • SELECT
        • SHOW
        • UPDATE
        • Arrays
        • Logical Operators and Conditional and Subquery Expressions
        • Table Expression and Join Support
        • Type Casts
      • Geospatial Capabilities
        • Uber H3 Hexagonal Modeling
      • Functions and Operators
      • System Table Functions
        • generate_random_strings
        • generate_series
        • tf_compute_dwell_times
        • tf_feature_self_similarity
        • tf_feature_similarity
        • tf_geo_rasterize
        • tf_geo_rasterize_slope
        • tf_graph_shortest_path
        • tf_graph_shortest_paths_distances
        • tf_load_point_cloud
        • tf_mandelbrot*
        • tf_point_cloud_metadata
        • tf_raster_contour_lines; tf_raster_contour_polygons
        • tf_raster_graph_shortest_slope_weighted_path
        • tf_rf_prop_max_signal (Directional Antennas)
        • ts_rf_prop_max_signal (Isotropic Antennas)
        • tf_rf_prop
      • Window Functions
      • Reserved Words
      • SQL Extensions
  • Heavy Immerse
    • Introduction to Heavy Immerse
    • Admin Portal
    • Control Panel
    • Working with Dashboards
      • Dashboard List
      • Creating a Dashboard
      • Configuring a Dashboard
      • Duplicating and Sharing Dashboards
    • Measures and Dimensions
    • Using Parameters
    • Using Filters
    • Using Cross-link
    • Chart Animation
    • Multilayer Charts
    • SQL Editor
    • Customization
    • Joins (Beta)
    • Chart Types
      • Overview
      • Bar
      • Bubble
      • Choropleth
      • Combo
      • Cross-Section
      • Contour
      • Gauge
      • Geo Heatmap
      • Heatmap
      • Histogram
      • Line
      • Linemap
      • New Combo
      • Number
      • Pie
      • Pointmap
      • Scatter Plot
      • Skew-T
      • Stacked Bar
      • Table
      • Text Widget
      • Wind Barb
  • HeavyRF
    • Introduction to HeavyRF
    • Getting Started
    • HeavyRF Table Functions
  • HeavyConnect
    • HeavyConnect Release Overview
    • Getting Started
    • Best Practices
    • Examples
    • Command Reference
    • Parquet Data Wrapper Reference
    • ODBC Data Wrapper Reference
  • HeavyML (BETA)
    • HeavyML Overview
    • Clustering Algorithms
    • Regression Algorithms
      • Linear Regression
      • Random Forest Regression
      • Decision Tree Regression
      • Gradient Boosting Tree Regression
    • Principal Components Analysis
  • Python / Data Science
    • Data Science Foundation
    • JupyterLab Installation and Configuration
    • Using HEAVY.AI with JupyterLab
    • Python User-Defined Functions (UDFs) with the Remote Backend Compiler (RBC)
      • Installation
      • Registering and Using a Function
      • User-Defined Table Functions
      • RBC UDF/UDTF Example Notebooks
      • General UDF/UDTF Tutorial Notebooks
      • RBC API Reference
    • Ibis
    • Interactive Data Exploration with Altair
    • Additional Examples
      • Forecasting with HEAVY.AI and Prophet
  • APIs and Interfaces
    • Overview
    • heavysql
    • Thrift
    • JDBC
    • ODBC
    • Vega
      • Vega Tutorials
        • Vega at a Glance
        • Getting Started with Vega
        • Getting More from Your Data
        • Creating More Advanced Charts
        • Using Polys Marks Type
        • Vega Accumulator
        • Using Transform Aggregation
        • Improving Rendering with SQL Extensions
      • Vega Reference Overview
        • data Property
        • projections Property
        • scales Property
        • marks Property
      • Migration
        • Migrating Vega Code to Dynamic Poly Rendering
      • Try Vega
    • RJDBC
    • SQuirreL SQL
    • heavyai-connector
  • Tutorials and Demos
    • Loading Data
    • Using Heavy Immerse
    • Hello World
    • Creating a Kafka Streaming Application
    • Getting Started with Open Source
    • Try Vega
  • Troubleshooting and Special Topics
    • FAQs
    • Troubleshooting
    • Vulkan Renderer
    • Optimizing
    • Known Issues and Limitations
    • Logs and Monitoring
    • Archived Release Notes
      • Release 6.x
      • Release 5.x
      • Release 4.x
      • Release 3.x
Powered by GitBook
On this page
Export as PDF
  1. APIs and Interfaces
  2. Vega
  3. Vega Reference Overview

projections Property

Previousdata PropertyNextscales Property

Last updated 5 years ago

Vega projections map longitude and latitude data to projected x and y coordinates. When working with geospatial data in OmniSci, you can use projections to define geographic points and regions.

General projections property JSON format:

"projections": [
       {
         "name": "<projectionName>",
         "type": "<projectionType>",
         "bounds": {
               "x": [<minLong>,<maxLong>],
               "y": [<minLat>,<maxLat>]
         }
       }
]

When you specify a projection, you must reference it in the using the transform object. For example, if you define the projection my_mercator_projection:

"projections": [
{
   "name": "my_mercator_projection",
   "type": "mercator",
   "bounds": {
     "x": [-120.0, 120.0],
     "y": [-20.0,20.0]
   }
 }
 ]

you then reference it as follows:

"marks": [
{
   "type": "symbol",
   "from": { "data": "fec_contributions_oct" },
   "properties": { ... elided ... }
   "transform": {
      "projection": "my_mercator_projection"
   }
 }
 ]

The projections specification has the following properties:

Property

Data Type

Required

Description

name

string

X

User-assigned name of the projection.

type

string

X

Projection type. Currently supported types:

  • mercator: Mercator map projection.

bounds

object

Specifies the longitude and latitude bounding box for the projection. Default values:

  • x: [-180.0, 180.0]

  • y: [-85.0, 85.0]

Example

Use Vega projection projection alongside array columns:

{
      "width": 1024,
      "height": 1024,
      "data": [
              {
                      "name": "table",
                      "sql": "SELECT rowid, coords[1] as x, coords[2] as y FROM cities WHERE coords[1] BETWEEN $minLon AND $maxLon AND coords[2] BETWEEN $minLat AND $maxLat"
              }
      ],
      "projections": [
      {
              "name": "projection",
              "type": "mercator",
              "bounds": {
              "x": [-120.0, 120.0],
              "y": [-20.0, 20.0]
              }
      }
      ],
      "scales": [
      ],
      "marks": [
              {
                      "type": "symbol",
                      "from": {"data": "table"},
                      "properties": {
                              "shape": "circle",
                              "xc": {
                                      "field": "x"
                              },
                              "yc": {
                                      "field": "y"
                              },
                              "fillColor": "darkblue",
                              "width": 25,
                              "height": 25
                      },
                      "transform": {
                              "projection": "projection"
                      }
              }
      ]
}
Marks Property