Gridlines not removed when setting tickMinStep

[morberg]

(I originally made a comment on the closed issue #1655, but it is probably better to handle this as a separate issue.)

When setting tickMinStep in Altair 4.1.0 the gridlines remain although the ticks are no longer shown. Is this a bug? I would expect the gridlines to disappear as well as shown in #1655 (comment) .

import altair as alt
import pandas as pd

df = pd.DataFrame({
    'x': range(5),
    'y': range(5)
})

alt.Chart(df).mark_point().encode(
    alt.X('x', axis=alt.Axis(tickMinStep=1.0)),
    alt.Y('y')
)

[jakevdp]

It looks like grid lines don't respond to tickMinStep. This may be a Vega-Lite bug – I'd suggest inquiring there.

To work around it, you can specify tickCount, e.g.

import altair as alt
import pandas as pd

df = pd.DataFrame({
    'x': range(5),
    'y': range(5)
})

alt.Chart(df).mark_point().encode(
    alt.X('x', axis=alt.Axis(tickMinStep=1.0, tickCount=4)),
    alt.Y('y')
)

[joelostblom]

It seems like this was fixed in VL, but has since then become an issue again. The progress can be followed in vega/vega-lite#9034. I'm closing this since there is nothing altair can do to fix this bug.