bug: plot_ibound method not working, grid is not shown

[aestrad-intera]

mv = flopy.plot.PlotMapView(model=gwf, layer=0, ax=ax)
mv.plot_ibound(alpha=0.8)

this does not plot ibound, grid is not shown on plot

[jlarsen-usgs]

@aestrad-intera

Do you have any more information? The plot_ibound method has not been changed/updated in a long time and has been fairly reliable. A minimal example would help in determining what the issue you are having is.

[jlarsen-usgs]

Also to plot the grid, call:

mv.plot_grid()

[aestrad-intera]

Thank you for your suggestion, Joshua. I agree that plot_ibound has been reliable, as I have never had any issue with it until now. This is a 2D, MF6, 1-layer model with all cells as active. I don't see anything wrong with my lines of code: fig, ax = plt.subplots(1, 1, figsize=(10, 8)) # fig.suptitle('',fontsize=18) mv = flopy.plot.PlotMapView(model=gwf, layer=0, ax=ax) for level, color in zip(levels, rgba): mv.contour_array(mf6_conc, levels=[level], colors=color, linewidths=2.0, alpha=1., linestyles='solid') mv.contour_array(pht3d_conc, levels=[level], colors=color, linewidths=2.0, alpha=1., linestyles='dashed') mv.plot_bc('WEL', color='red') mv.plot_bc('CHD', color='blue') mv.plot_ibound(alpha=0.8) plt.show() ax.set_title(f'Toluene concentrations after {day} days',fontsize=14) # ax.set_axis_off() fig.tight_layout() That code produces: [image: image.png] See there is no grid. But your suggestion works: fig, ax = plt.subplots(1, 1, figsize=(10, 8)) # fig.suptitle('',fontsize=18) mv = flopy.plot.PlotMapView(model=gwf, layer=0, ax=ax) mv.plot_grid(alpha=0.5) for level, color in zip(levels, rgba): mv.contour_array(mf6_conc, levels=[level], colors=color, linewidths=2.0, alpha=1., linestyles='solid') mv.contour_array(pht3d_conc, levels=[level], colors=color, linewidths=2.0, alpha=1., linestyles='dashed') mv.plot_bc('WEL', color='red') mv.plot_bc('CHD', color='blue') # mv.plot_ibound(alpha=0.8) plt.show() ax.set_title(f'Toluene concentrations after {day} days',fontsize=14) # ax.set_axis_off() fig.tight_layout() [image: image.png] Thanks, Andres

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On Fri, Sep 5, 2025 at 4:40 PM Joshua Larsen ***@***.***> wrote: *jlarsen-usgs* left a comment (modflowpy/flopy#2592) <#2592 (comment)> Also to plot the grid, call: mv.plot_grid() — Reply to this email directly, view it on GitHub <#2592 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/A52MYOIOLKNX2FP4LQM6SBT3RH7OXAVCNFSM6AAAAACFYIDIY2VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZTENJZHAZDKMRZGE> . You are receiving this because you were mentioned.Message ID: ***@***.***>

[wpbonelli]

@aestrad-intera could you provide the model you are using with this plotting code, or a simple one reproducing the issue?

[jlarsen-usgs]

@aestrad-intera plot_ibound() masks out the active cells and plots inactive cells as black and vertical pass through cells as red. The reason you're not seeing anything when you use plot_ibound(), is that all cells in your model are active which means that by the default behavior they are masked (which is the behavior that we expect).