Add a 2 cases if() command to Raster Calculator

[qgib]

Author Name: alobo - (alobo -)
Original Redmine Issue: 4476

Redmine category:rasters

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An if() command with 2 cases output would be most useful:

if(condition, result1, result2)

where the output value is result1 if condition==T and result2 otherwise.

Agus

[qgib]

Author Name: alobo - (alobo -)

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• category_id was configured as Rasters
• fixed_version_id was configured as Version 1.7.1
• operating_system was changed from to all

[qgib]

Author Name: Tim Sutton (Tim Sutton)

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• fixed_version_id was changed from Version 1.7.1 to Version 1.7.2

[qgib]

Author Name: Giovanni Manghi (@gioman)

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• fixed_version_id was changed from Version 1.7.2 to Version 1.7.3

[qgib]

Author Name: Giovanni Manghi (@gioman)

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• fixed_version_id was changed from Version 1.7.3 to Version 1.7.4

[qgib]

Author Name: Giovanni Manghi (@gioman)

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• fixed_version_id was changed from Version 1.7.4 to Version 2.0.0

[qgib]

Author Name: Pirmin Kalberer (Pirmin Kalberer)

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• fixed_version_id was changed from Version 2.0.0 to Future Release - Nice to have

[qgib]

Author Name: Médéric RIBREUX (Médéric RIBREUX)

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Hello, bug triage...

the raster calculator can handle conditions but the expression is not so easy to understand:

("elevation@1" < 50) * 1 + ("elevation@1" >= 50) * 2

will make cells with a value less than 50 have a value of 1 and cells with a value greater than or equal to 50 have a value of 2.

Was your feature request about a way to have conditions in the raster calculator or about the syntax of the condition ?

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• status_id was changed from Open to Feedback

[qgib]

Author Name: alobo - (alobo -)

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Well, that syntax is really odd, I had not even thought on it.
I guess that
if(condition, result1, result2)
would be a lot more transparent and easier to remember

[qgib]

Author Name: Giovanni Manghi (@gioman)

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• easy_fix was configured as 0

[qgib]

Author Name: Alister Hood (@AlisterH)

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Is this ticket really waiting for feeback? Of what in particular?
Perhaps it should be closed, maybe as a duplicate of #16517.

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• description was changed from An if() command with 2 cases output would be most useful:

if(condition, result1, result2)

where the output value is result1 if condition==T and result2 otherwise.

Agus to An if() command with 2 cases output would be most useful:

if(condition, result1, result2)

where the output value is result1 if condition==T and result2 otherwise.

Agus

[github-actions]

The QGIS project highly values your report and would love to see it addressed. However, this issue has been left in feedback mode for the last 14 days and is being automatically marked as "stale".
If you would like to continue with this issue, please provide any missing information or answer any open questions. If you could resolve the issue yourself meanwhile, please leave a note for future readers with the same problem and close the issue.
In case you should have any uncertainty, please leave a comment and we will be happy to help you proceed with this issue.
If there is no further activity on this issue, it will be closed in a week.

[AlisterH]

I don't think this ticket was really waiting for feedback.
The question was asked "Was your feature request about a way to have conditions in the raster calculator or about the syntax of the condition?"
The answer was that the request was about the way to have conditions, but now that we know there is a way, the syntax is "weird" and an if() syntax would be more useful.

That's not to say that keeping the ticket open will achieve anything...

[AlisterH]

I see #16517 is still open - maybe this can be considered a duplicate of it, and closed.