topic Re: ArcGIS Pro 3.4.2: Reclassifying a raster into two classes results in three, in ArcGIS Pro Questions

ArcGIS Pro 3.4.2: Reclassifying a raster into two classes results in three,

JamalNUMAN — Tue, 06 May 2025 11:36:09 GMT

ArcGIS Pro 3.4.2: Reclassifying a raster into two classes results in three,

In the screenshots below, I attempted to classify a raster into two classes using the “Reclassify” tool, but the output ends up with three classes.

What could be causing this issue?

The data raster is attached.

Re: ArcGIS Pro 3.4.2: Reclassifying a raster into two classes results in three,

JonM32 — Tue, 06 May 2025 12:13:25 GMT

@JamalNUMAN The value of 0 is for the No Data cell in the raster.

I'd try running the tool again with the check box marked for 'change missing values to nodata' and see what happens.

Otherwise, you could assign a value for the no data cell, to either 1 or 2 value you're working with or something else.

Jon

Re: ArcGIS Pro 3.4.2: Reclassifying a raster into two classes results in three,

JamalNUMAN — Wed, 07 May 2025 06:56:31 GMT

I set the 'New' value for NODATA to 7. However, the Reclassify tool produces 4 classes, even though the number of classes is set to 3, as shown in the screenshots below.

What could be the reason behind the class with the value '0'?

Re: ArcGIS Pro 3.4.2: Reclassifying a raster into two classes results in three,

JonM32 — Wed, 07 May 2025 11:32:28 GMT

I'm honestly not sure.

Maybe check the statistics of the dataset you're reclassifying to see if the values being changed are within it.

Or try to reclassifying using different ranges of values and see what happens?

Re: ArcGIS Pro 3.4.2: Reclassifying a raster into two classes results in three,

JamalNUMAN — Thu, 08 May 2025 07:03:46 GMT

Does it indicate anything that the cell taking the value 0 originally had a value of -0.149068, which is the minimum value in the original raster? Why is a separate class automatically created for this value?

Re: ArcGIS Pro 3.4.2: Reclassifying a raster into two classes results in three,

JonM32 — Thu, 08 May 2025 11:47:27 GMT

If I had to guess, it's a rounding thing that occurs when the tool is run. You could always try to reclass a value below the -0.149068 and see what happens. For example, reclass anything from -1 to 0.744594 to 1

Re: ArcGIS Pro 3.4.2: Reclassifying a raster into two classes results in three,

JamalNUMAN — Fri, 09 May 2025 04:49:16 GMT

I changed -0.149068 to -0.15 in the classification, and the classes were then created as expected.
This seems like strange behavior in Pro—could it be a bug? Why isn’t -0.149068 recognized as a value in the first class?

Re: ArcGIS Pro 3.4.2: Reclassifying a raster into two classes results in three,

JonM32 — Fri, 09 May 2025 11:55:40 GMT

Not sure why - that's likely how they wrote the code to assess values.

Glad it worked for you!

Jon