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NV5 Geospatial Blog

Each month, NV5 Geospatial posts new blog content across a variety of categories. Browse our latest posts below to learn about important geospatial information or use the search bar to find a specific topic or author. Stay informed of the latest blog posts, events, and technologies by joining our email list!



NV5 at ESA’s Living Planet Symposium 2025

NV5 at ESA’s Living Planet Symposium 2025

9/16/2025

We recently presented three cutting-edge research posters at the ESA Living Planet Symposium 2025 in Vienna, showcasing how NV5 technology and the ENVI® Ecosystem support innovation across ocean monitoring, mineral exploration, and disaster management. Explore each topic below and access the full posters to learn... Read More >

Monitor, Measure & Mitigate: Integrated Solutions for Geohazard Risk

Monitor, Measure & Mitigate: Integrated Solutions for Geohazard Risk

9/8/2025

Geohazards such as slope instability, erosion, settlement, or seepage pose ongoing risks to critical infrastructure. Roads, railways, pipelines, and utility corridors are especially vulnerable to these natural and human-influenced processes, which can evolve silently until sudden failure occurs. Traditional ground surveys provide only periodic... Read More >

Geo Sessions 2025: Geospatial Vision Beyond the Map

Geo Sessions 2025: Geospatial Vision Beyond the Map

8/5/2025

Lidar, SAR, and Spectral: Geospatial Innovation on the Horizon Last year, Geo Sessions brought together over 5,300 registrants from 159 countries, with attendees representing education, government agencies, consulting, and top geospatial companies like Esri, NOAA, Airbus, Planet, and USGS. At this year's Geo Sessions, NV5 is... Read More >

Not All Supernovae Are Created Equal: Rethinking the Universe’s Measuring Tools

Not All Supernovae Are Created Equal: Rethinking the Universe’s Measuring Tools

6/3/2025

Rethinking the Reliability of Type 1a Supernovae   How do astronomers measure the universe? It all starts with distance. From gauging the size of a galaxy to calculating how fast the universe is expanding, measuring cosmic distances is essential to understanding everything in the sky. For nearby stars, astronomers use... Read More >

Using LLMs To Research Remote Sensing Software: Helpful, but Incomplete

Using LLMs To Research Remote Sensing Software: Helpful, but Incomplete

5/26/2025

Whether you’re new to remote sensing or a seasoned expert, there is no doubt that large language models (LLMs) like OpenAI’s ChatGPT or Google’s Gemini can be incredibly useful in many aspects of research. From exploring the electromagnetic spectrum to creating object detection models using the latest deep learning... Read More >

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Hash syntax for accessing children in (New) Graphics

Anonym
A useful feature of (New) Graphics (NG) is the ability to access a component of a visualization by name using hash syntax. This behavior is derived from the GetByName method implemented by most container classes in Object Graphics. For example, here I have a window that holds a plot of a Bessel J function:
x = findgen(100)/5
y = beselj(x)
w = window()
p = plot(x, y, color='red', name='bessel_j0', /current)
Note that I gave the plot a name. (The default name of a plot is ‘Plot’, or if more than one plot is present in a window, ‘Plot n’, where n = 1,2,3,…; likewise, ‘Surface’ for a surface, ‘Image’ for an image, etc.) Now discard the reference to the plot (maybe, e.g., it fell out of scope):
p = !null
So I now can’t access the properties of the plot. Or can I?! Retrieve the reference to the plot, by its name, from the window using hash syntax:
q = w['bessel_j0']
and use the recovered reference to change the color of the plot:
q.color = 'green'
Neat! I use this feature of NG frequently, especially to get access to the axes of a plot, post-creation. For example, to hide the top and right axes of the plot above, try:
q['axis2'].hide = 1
q['axis3'].hide = 1
In NG, axes are numbered starting at zero with the bottom axis and increasing clockwise (the left axis is index 1, etc.). In a subsequent post, I’ll talk about the very handy GETWINDOWS function for when you don’t have a reference to the window object holding a visualization.
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