topic Reclassifying a raster produces �??weird�?� values! in ArcGIS Spatial Analyst Questions

Reclassifying a raster produces �??weird�?� values!

JamalNUMAN — Fri, 25 May 2012 19:21:46 GMT

Reclassifying a raster produces �??weird�?� values!

I wanted to reclassify the raster shown in the screenshot below:

[ATTACH=CONFIG]14663[/ATTACH], [ATTACH=CONFIG]14663[/ATTACH], [ATTACH=CONFIG]14664[/ATTACH][ATTACH=CONFIG]14665[/ATTACH]

1. The maximum cell value in the raster doesn�??t match that one shown by the �??reclassify�?� tool! How come?
2. How come the reclassify tool doesn�??t see the maximum value existing in the original raster and thus more values appear rather than the ranges specified on the reclassification!
How to overcome this problem? How to let the �??reclassify�?� tool see all the values of the original raster?
Thank you for the help,
Best
Jamal

Re: Reclassifying a raster produces �??weird�?� values!

Anonymous User — Fri, 25 May 2012 20:26:33 GMT

Original User: SaultDon

That is a strange issue..

Can you increase the sampling size to anything higher than the "Count"?

Your count is 343809 so try to use a sampling size of 345000, for example.

I think by default your sampling is set to ~10,000.

Re: Reclassifying a raster produces �??weird�?� values!

JamalNUMAN — Sat, 26 May 2012 07:32:43 GMT

That is a strange issue..

Can you increase the sampling size to anything higher than the "Count"?

Your count is 343809 so try to use a sampling size of 345000, for example.

I think by default your sampling is set to ~10,000.

Thank you for the answer.
I�??m not sure why the �??reclassify�?� doesn�??t read the values from the input raster! That�??s really frustrating!
How can I switch the sampling size? Could you please elaborate more?

[ATTACH=CONFIG]14668[/ATTACH], [ATTACH=CONFIG]14669[/ATTACH]

Best
Jamal

Re: Reclassifying a raster produces �??weird�?� values!

Anonymous User — Mon, 28 May 2012 16:54:36 GMT

Original User: SaultDon

Look back at your first post, in the first screenshot.

The sampling button is in the window where you modify the 'class ranges'.

I think you press the "Classify" button inside the "Reclassify" tool.

Re: Reclassifying a raster produces �??weird�?� values!

JamalNUMAN — Mon, 28 May 2012 21:24:04 GMT

Look back at your first post, in the first screenshot.

The sampling button is in the window where you modify the 'class ranges'.

I think you press the "Classify" button inside the "Reclassify" tool.

Many thanks for the prompt answer.
Sorry but I couldn�??t know how to change the sampling size. The screenshot is below.
How to change the sample?

[ATTACH=CONFIG]14691[/ATTACH]

Re: Reclassifying a raster produces �??weird�?� values!

Anonymous User — Tue, 29 May 2012 20:42:04 GMT

Original User: erictrice

Jamal,

Please follow the steps in the knowledge base article to resolve this issue.

HowTo: Compute the histogram with all the unique values, when using the classified renderer

Regards,
Eric

Re: Reclassifying a raster produces �??weird�?� values!

JamalNUMAN — Fri, 01 Jun 2012 18:55:38 GMT

Jamal,

Please follow the steps in the knowledge base article to resolve this issue.

HowTo: Compute the histogram with all the unique values, when using the classified renderer

Regards,
Eric

Many thanks for the help. I�??ll try it and let you know

[ATTACH=CONFIG]14873[/ATTACH]

Best

Jamal