Help with chart expression

[#1]

I am looking for some advice on the following scenario:

LOAD * INLINE [
Item, Pattern1, Pattern2, Pattern2Qty
A, 1, 1, 100
A, 1, 1, 150
A, 1, 2, 125
A, 1, 2, 200
A, 1, 2, 250
B, 2, 1, 50
B, 2, 1, 300
B, 2, 2, 150
B, 2, 2, 200
];

I am looking for the Max of Pattern2Qty (grouped by Item), where Pattern1 = Pattern2. The result should look like this..

A   150

B   200

Thank you for taking the time to help me....

[tresesco · Accepted solution]

Straight table:

Dimension: item

Exp:  Max(If(Pattern1=Pattern2, Pattern2Qty))

[sunny_talwar]

Or may be create a flag in the script

LOAD *,

    If(Pattern1 = Pattern2, 1, 0) as Flag

LOAD * INLINE [
Item, Pattern1, Pattern2, Pattern2Qty
A, 1, 1, 100
A, 1, 1, 150
A, 1, 2, 125
A, 1, 2, 200
A, 1, 2, 250
B, 2, 1, 50
B, 2, 1, 300
B, 2, 2, 150
B, 2, 2, 200
];

and then this

Max({<Flag = {1}>} Pattern2Qty)

[#4]

It seems that I am always over thinking it!  Thank you, this worked perfectly.