# Weekly Challenge

Solve the challenge, share your solution and summit the ranks of our Community!
###### IDEAS WANTED

We're actively looking for ideas on how to improve Weekly Challenges and would love to hear what you think!

Submit Feedback
We've recently made an accessibility improvement to the community and therefore posts without any content are no longer allowed. Please use the spoiler feature or add a short message in the message body in order to submit your weekly challenge.

## Challenge #113: Interpolating Spatial Grid Values

Highlighted
Alteryx

So many different solutions to last week's Challenge have been posted here!

This week's Challenge riffs off a process typically used in spatial analysis with raster inputs: interpolation.  In this Challenge, you are provided with two inputs: a polygon representing the island of Maui (hey, there's still snow in the forecast here in CO...can you blame me for picking a beachy location?) and a table of values representing the elevation measurements for 500 m x 500 m grid cells (much like a Digital Elevation Model).  However, some grid cells contain a value of 0.  We'll use some spatial tools to interpolate, or estimate, the values of the cells containing 0 from a "nearest neighborhood" or surrounding cell values.

First, build a 500 m x 500 m grid around the island of Maui.   Then, interpolate the missing value using the average of the known measurements from the surrounding cells, or "neighborhood".  Use a neighborhood of the 8 nearest surrounding cells in a unique cardinal direction (see example below; a neighborhood of a cell containing a 0 is outlined in blue. In this example, the new interpolated value of the center cell would be 61.5). Should a missing value be located on the edge, use only the nearest cells in a unique cardinal direction, even if 8 values are not used for the calculation.

Hint: Grid cell Grd37_68 is column 37, row 68. The Grid tool starts with column 0.

Highlighted
12 - Quasar

Fun spatial exercise!

Highlighted
16 - Nebula

I opted for a non-spatial technique.

EDIT: I added a spatial technique as well.

Spoiler

Highlighted
11 - Bolide

It's a good challenge when I start with a sheet of paper and pencil  to figure out the logic, before any tools get dropped onto a canvas.

Spoiler
Highlighted
7 - Meteor

Highlighted
Inactive User
Not applicable

Highlighted
12 - Quasar
Spoiler
Took me a while to wrap my head around this one! My way of solving it felt quite cumbersome, curious to see what better ways are out there.

Highlighted
8 - Asteroid

Here's my submission.

This was a great way for me to get more familiar with some of the Spatial tools, thanks!

Spoiler
Highlighted
8 - Asteroid

Slowly but surely learning how to use spatial tools

Spoiler
Highlighted
14 - Magnetar

My solution! Included both a spatial and a non-spatial solution 🙂 Fun one!

Spoiler

Cheers,

NJ