Fill in 0 with last value in another column

[LuciaS1]

Hi, colud you help me with DAX code. I need to create new column with values from another one. I need to repleace 0 value with first value until new value is there. 

Pomocny	Stlpec1
1000000	1000000
0	1000000
0	1000000
0	1000000
0	1000000
0	1000000
0	1000000
0	1000000
0	1000000
0	1000000
0	1000000
645826,7	645826,7
0	645826,7
0	645826,7
0	645826,7
0	645826,7
0	645826,7
0	645826,7
0	645826,7
0	645826,7
0	645826,7
0	645826,7
0	645826,7
311287,1	311287,1
0	311287,1
0	311287,1
0	311287,1
0	311287,1
0	311287,1
0	311287,1
0	311287,1
0	311287,1
0	311287,1
0	311287,1
0	311287,1
0	311287,1

I tried code like tihis but it is not working. 

Measure =

IF (

    SELECTEDVALUE ( 'Hárok1'[Pomocny] ) = 0,

    VAR a =

        MAXX (

            FILTER (

                ALL ( 'Hárok1' ),

                [Index] < SELECTEDVALUE ( 'Hárok1'[Index] )

                    && 'Hárok1'[Pomocny] <> 0

            ),

            [Index]

        )

    RETURN

        MAXX ( FILTER ( ALL ( 'Hárok1' ), 'Hárok1'[Index] = a ), 'Hárok1'[Pomocny] ),

    SELECTEDVALUE ( 'Hárok1'[Pomocny] )).

Thanks 

[Greg_Deckler · Accepted solution]

@LuciaS1 In Power Query, add an Index column. Then you can do this. PBIX is attached below signature.

Measure = 
    VAR __Index = MAX('Harok1'[Index])
    VAR __Value = MAX('Harok1'[Pomocny])
    VAR __Result = 
        IF(
            __Value <> 0,
            __Value,
                VAR __Previous = MAXX(FILTER(ALL('Harok1'), [Index] < __Index && [Pomocny] <> 0), [Index])
                VAR __Result = MINX(FILTER(ALL('Harok1'), [Index] = __Previous), [Pomocny])
            RETURN
                __Result
        )
RETURN
    __Result