Custom column M language filter formula translation from desktop new column formula

Hi Vauban , 

You are using DAX instead of power query. If you want to achieve this in power query, you could refer to below code

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WSlTSUTIEYVOlWB0E18gAzjUCCRmBuUkwxSg8UzgPpNQChWcG5xmDMTIPaGYsAA==", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type text) meta [Serialized.Text = true]) in type table [name = _t, id = _t, amount = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"name", type text}, {"id", Int64.Type}, {"amount", Int64.Type}}),
    #"Grouped Rows" = Table.Group(#"Changed Type", {"name", "id"}, {{"mivx", each List.Min([amount]), type number}, {"all", each _, type table [name=text, id=number, amount=number]}}),
    #"Expanded all" = Table.ExpandTableColumn(#"Grouped Rows", "all", {"amount"}, {"amount"})
in
    #"Expanded all"

If you want to use your expression, you need to create calculated column instead of power query, you need to create like below

 In addition, you also could use measure to achieve this, which will show in table visual, you could try below expression

Measure 2 = CALCULATE(MIN(t[amount]), ALLEXCEPT(t,t[name],t[id]))

Best Regards,
Zoe Zhi

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