Replace two round brackets (( by three round brackets ((( and same for closing brackets

You could try and be more specific in catching the (( and )) in a string replacer.

For example including the parantheses when replacing the POLYGON to MULTIPOLYGON.

The closing one you could include the ; sign to specify those )). I’m assuming that a multipolygon will always end with a ; so it should always be there at the end brackets?

To visualise it:

Hope it’s clear!

Hi,

The cleanest way would be to create the polygon geometry with GeometryReplacer, Aggregate the feature and then extract the Geometry back to WKT with the GeometryExtractor. 

To handle the attribute after the semicolon you could use a StringSercher to store the info in a temp attribute and then appended it to the new WKT using a StringConcatenator at the end.

 

Thanks for two good suggestions!

I had to go with the string replacer option though... 

The Aggregator & GeometryExtractor suggestion doesn’t solve my problem, as it makes the WKT field look like this, so I’m further from my objective:

GEOMETRYCOLLECTION (MULTIPOLYGON (((3.751446328848148 51.09789238333794,3.7514744771186774 51.09785395106413,3.7515454118479563 51.09787454834335)),((3.7486227439488014 51.10188366613414,3.7471867226749627 51.101468672794745,3.745208081250554 51.1041693453312))),POLYGON ((3.743757864908372 51.08620899834685,3.744266505912946 51.0833952986076,3.7433015994552856 51.08332946064444)))

I do agree though that this would be the cleaner solution, if it worked… When I export a shapefile as CSV-WKT in QGIS, it only gives me multipolygons, even if there are also single polygons present. So the best solution would be that the GeometryExtractor would give me only MULTIPOLYGON’s too. 

You could try and be more specific in catching the (( and )) in a string replacer.

 

For example including the parantheses when replacing the POLYGON to MULTIPOLYGON.

The closing one you could include the ; sign to specify those )). I’m assuming that a multipolygon will always end with a ; so it should always be there at the end brackets?

 

To visualise it:

 

Hope it’s clear!

I was rejoicing too soon… I cannot put two StringReplacers in a row (FME crashes during runtime then, “error during translation”) and the basic StringReplacer can only change one thing in a row. Which transformer is that you are using in the screenshot? I hope it’s one that is available yet in FME 2025.0. 

Oh no! I was using the StringReplacer in FME 2026.1. It was updated to be able to change multiple string replacements in one transformer in version FME 2025.2..

Do you run it with feature caching? You could try it without or collapse some bookmarks so not so much data will be cached?

I do run it with feature caching on, but even without caching it crashes. And at the moment there are 59 objects involved, so not a huge data load I would think. 

I guess I’ll have to wait until we switch to a higher version of ArcGIS Enterprise > a higher version of ArcGIS Pro > a higher version of the workbench. Because we have FME through the ArcGIS Data Interop license... 

Hello @tanjabwzc ,

To replace round brackets or any other regex control characters, add a backslash in front of the character (ie. \(\( to match (( in text)

As you are using a version of FME where the StringReplacer does not allow multiple string replacements in one transformer, I would recommend the StringPairReplacer instead if you want to continue with your original idea of text replacement.

This transformer is similar to StringReplacer but allows for multiple string replacements specified using a space separated list of replacement key-value pairs. Attached is a workspace demonstrates this approach.

I have also added ​an example of @frro‘s excellent suggestion of using the Aggregator and GeometryExtractor to demonstrate it can create the output you want. This method may be more suitable if the input geometry may not always be polygons.

I hope this information helps.

​

I’m looking for a solution that will also last after I upgrade, and looking up information on StringPairReplacer, I found out that it was deprecated in 2025.2: Bring back StringPairReplacer | Community

I think replacing the geometry and aggregating then extracting as WKT should work, you just need to exclude the geometries that are already multipolygons to avoid creating collections