"Object is not a ConcatenatedOperation" error

[dvargas74]

Hi,

I'm getting the error "Object is not a ConcatenatedOperation" when C API function "proj_concatoperation_get_step_count" is called with the followings pipelines:

proj=pipeline step inv proj=somerc lat_0=46.9524055555556 lon_0=7.43958333333333 k_0=1 x_0=600000 y_0=200000 ellps=bessel step proj=hgridshift grids=ch_swisstopo_CHENyx06_ETRS.tif step proj=vgridshift grids=ch_swisstopo_chgeo2004_ETRS89_LN02.tif multiplier=1 step inv proj=vgridshift grids=ch_swisstopo_chgeo2004_ETRS89_LHN95.tif multiplier=1 step proj=push v_3 step proj=cart ellps=GRS80 step proj=helmert x=-674.374 y=-15.056 z=-405.346 step inv proj=cart ellps=bessel step proj=pop v_3 step proj=somerc lat_0=46.9524055555556 lon_0=7.43958333333333 k_0=1 x_0=2600000 y_0=1200000 ellps=Bessel

proj=pipeline step inv proj=somerc lat_0=46.9524055555556 lon_0=7.43958333333333 k_0=1 x_0=600000 y_0=200000 ellps=bessel step proj=push v_3 step proj=cart ellps=bessel step proj=helmert x=674.374 y=15.056 z=405.346 step inv proj=cart ellps=GRS80 step proj=pop v_3 step proj=vgridshift grids=ch_swisstopo_chgeo2004_ETRS89_LN02.tif multiplier=1 step inv proj=vgridshift grids=ch_swisstopo_chgeo2004_ETRS89_LHN95.tif multiplier=1 step proj=push v_3 step proj=cart ellps=GRS80 step proj=helmert x=-674.374 y=-15.056 z=-405.346 step inv proj=cart ellps=bessel step proj=pop v_3 step proj=somerc lat_0=46.9524055555556 lon_0=7.43958333333333 k_0=1 x_0=2600000 y_0=1200000 ellps=Bessel

These pipelines are created by PROJ when doing the following transformation for Switzerland:

EPSG:21781+EPSG:5728 - CH1903 / LV03 + LN02 height

to

EPSG:2056+EPSG:5729 - CH1903+ / LV95 + LHN95 height

The version of PROJ library is 9.6.0 and it's running on Windows 11 operating system

[rouault]

If you try proj_concatoperation_get_step_count() on a PJ* object created with proj_create(the_pipeline_string), then it is expected. proj_concatoperation_get_step_count() will only work on objects returned by proj_create_crs_to_crs()

[dvargas74]

It works with other pipelines, this is the first time I got this error.