cannot translate vega-light color condition to altair - altair

Question

I have this vlspec (it is working)
I need to translate it to altair
vlspec.encoding.color =
{
"scale": {
"type": "threshold",
"domain": [
"< 10",
"10 - 70",
"≥ 70"
],
"range": [
"#cb5047",
"#f1ad4b",
"#486d49"
]
},
"condition": [
{
"test": {
"field": "rate",
"lt": 10
},
"value": "#cb5047"
},
{
"test": {
"field": "rate",
"lt": 70
},
"value": "#f1ad4b"
},
{
"test": {
"field": "rate",
"gte": 70
},
"value": "#486d49"
}
]
}
I trying a lot of options for alt.Condition, but failed to translate this to altair. Can somebody help please?

Answer 1

Altair uses Vega-Lite 4.8, in which it is not permitted to include a "scale" specification in a "value" encoding (it has no effect anyway). Once you take that out, you can use your Vega-Lite specification directly in your Altair chart. For example:
import altair as alt
import pandas as pd
df = pd.DataFrame({
'x': [1, 2, 3, 4],
'rate': [5, 20, 40, 80]
})
color = {
"condition": [
{
"test": {
"field": "rate",
"lt": 10
},
"value": "#cb5047"
},
{
"test": {
"field": "rate",
"lt": 70
},
"value": "#f1ad4b"
},
{
"test": {
"field": "rate",
"gte": 70
},
"value": "#486d49"
}
]
}
alt.Chart(df).mark_point().encode(
x='x',
y='rate',
color=color
)