Select row with MAX value per category Power BI

Question

How to select row with max value per category in M of Power BI. Suppose we have table:

+----------+-------+------------+
| Category | Value |    Date    |
+----------+-------+------------+
| apples   |     1 | 2018-07-01 |
| apples   |     2 | 2018-07-02 |
| apples   |     3 | 2018-07-03 |
| bananas  |     7 | 2018-07-04 |
| bananas  |     8 | 2018-07-05 |
| bananas  |     9 | 2018-07-06 |
+----------+-------+------------+

Desired results are:

+----------+-------+------------+
| Category | Value |    Date    |
+----------+-------+------------+
| apples   |     3 | 2018-07-03 |
| bananas  |     9 | 2018-07-06 |
+----------+-------+------------+

Here is a start table for PBI:

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WSiwoyEktVtJRMgRiIwNDC10Dc10DQ6VYHSQ5I2Q5I1Q5Y2Q5Y7BcUmIeEIIkzZElTdAkLZAlTdEkLZElzZRiYwE=", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type text) meta [Serialized.Text = true]) in type table [Category = _t, Value = _t, Date = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Category", type text}, {"Value", Int64.Type}, {"Date", type date}})
in
    #"Changed Type"

I wonder if there is a way to come to desired results in subsequent steps within only one table, by adding some magic column IsMax:

+----------+-------+------------+-------+
| Category | Value |    Date    | IsMax |
+----------+-------+------------+-------+
| apples   |     1 | 2018-07-01 |     0 |
| apples   |     2 | 2018-07-02 |     0 |
| apples   |     3 | 2018-07-03 |     1 |
| bananas  |     7 | 2018-07-04 |     0 |
| bananas  |     8 | 2018-07-05 |     0 |
| bananas  |     9 | 2018-07-06 |     1 |
+----------+-------+------------+-------+

Answer 1

I ended up getting MAX per category through index. Idea described here: https://stackoverflow.com/a/51498237/1903793

Approach #1 is one-liner snipped in R transformation:

library(dplyr)
output <- dataset %>% group_by(Category) %>% mutate(row_no_by_category = row_number(desc(Date)))

Approach #2, done completely in PBI:

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WSiwoyEktVtJRMgRiIwNDC10Dc10DQ6VYHSQ5I2Q5I1Q5Y2Q5Y7BcUmIeEIIkzZElTdAkLZAlTdEkLZElzZRiYwE=", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type text) meta [Serialized.Text = true]) in type table [Category = _t, Value = _t, Date = _t]),
    #"Grouped rows" = Table.Group(Source, {"Category"}, {{"NiceTable", each Table.AddIndexColumn(Table.Sort(_,{{"Date", Order.Descending}} ), "Index",1,1), type table}} ),
    #"Expanded NiceTable" = Table.ExpandTableColumn(#"Grouped rows", "NiceTable", {"Value", "Date", "Index"}, {"Value", "Date", "Index"}),
    #"Filtered Rows" = Table.SelectRows(#"Expanded NiceTable", each ([Index] = 1))
in
    #"Filtered Rows"