CPCHOP(1)

💖 CPCHOP(1) 💖

okay bestie, welcome to the cpchop manual page — that's a User Commands page, section 1, and honestly? she's iconic. 🎀

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✨ NAME ✨

cpchop — Upscale simple statistics. that's it, that's the whole vibe. 🫶

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🌸 SYNOPSIS 🌸

cpchop gridfilename=cornerpointgrid.grdecl [option=value]

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🦋 DESCRIPTION 🦋

so basically, cpchop is a little utility for doing subsampling and property analysis of Eclipse grid files. the way it usually comes up is files generated in SBED or ReservoirStudio — but lowkey she's not picky, she works on all corner point grids that have a box shape and vertical pillars. no gatekeeping here. 💅

here's an example of her in her natural habitat:

cpchop gridfilename=HugeReservoirStudioGrid.grdecl subsamples=100 ilen=5 jlen=5 zlen=5

like. look at her go. 😭

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👑 OPTIONS 👑

one bullet per option, bestie, and yes I'm giving you ALL of them, no skipping the boring ones:

• subsamples — how many subsamples you want. defaults to 1.
• filebase — if you supply this, grdecl-files get written out for each subsample, named using this filebase. it may include directory names, so go off with your paths. ✨
• resultfile — the name of a textfile to output the table of results per subsample to.
• ilen — length in the i-direction of the subsample, specified in number of cells. defaults to all cells in the i-direction.
• jlen — length in the j-direction of the subsample, specified in number of cells. defaults to all cells in the j-direction.
• zlen — length in the z-direction of the subsample, specified in the grid's length unit (typically cm or m). defaults to full height.
• imin — can be used to limit the search area for random subsamples. defaults to the minimum i in the inputgrid (full model).
• imax — can be used to limit the search area for random subsamples. defaults to the maximum i in the inputgrid (full model).
• jmin — analog to imin, but in the j-direction. defaults to the minimum j in the inputgrid (full model).
• jmax — analog to imax, but in the j-direction. defaults to the maximum j in the inputgrid (full model).
• zmin — analog to imin, but in the z-direction and specified in the grid's length unit. defaults to the minimum in the inputgrid.
• zmax — analog to imax, but in the z-direction and specified in the grid's length unit. defaults to the maximum in the inputgrid.
• upscale — boolean for whether to do upscaling on the subsamples, either true or false. if your whole objective is just to get a grdecl-file for the subsample, set this to false for the run time, bestie, save yourself the wait. defaults to true.
• bc — boundary condition type for upscaling, either fixed or periodic. defaults to fixed.
• resettoorigin — if true, the outputted grdecl-file will have its ZCORN-values and COORDS-values shifted so the model is defined at the origin. if false, the outputted grdecl-file stays in its original position. defaults to true.
• seed — provide a seed number. defaults to 0.
• minperm — minimum permeability. defaults to 1e-9.
• dips — whether to do dip averaging. outputs dip and azimuth for each subsample. defaults to false.
• azimuthdisplacement — add or subtract a value for dip. assumes dips is set to true. defaults to zero.
• satnumvolumes — count volumes per satnum/rocktype. defaults to false.
• mincellvolume — ignore cells with volume below the threshold. defaults to 1e-9.
• endpoints — upscale saturation end-points. defaults to false.
• cappres — upscale capillary pressure. defaults to false.
• rock_list — provide a rock list for end-point upscaling.
• anisotropirocks — directional saturation functions. defaults to false.

💀 not me listing twenty-five options like it's nothing. but she ate, and you're gonna remember all of them now, periodt.

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🐛 REPORTING BUGS 🐛

found a bug? don't suffer in silence, bestie. report it on the github repository:

https://github.com/OPM/opm-upscaling/issues

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🌈 SEE ALSO 🌈

• upscale_perm

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and that's the whole page, bestie 💖

this was cpchop version 2023.10, from October 2023. go forth and subsample responsibly. 🧚✨