Special cases for minimum()

Dear HANA Experts.

Please find the below sample data and attached my model also.

Scenario 1 : I want to calculate the minimum value where the depth value is less than or equal to 0 specific to SRPNO, then Minimum is 0. (SRPNO = 2001). If all records are less than 0 and 0 is not there, then Min should be 0.

Scnario 2 : If the depth value is Negative to positive values (-5,-2, 0, 1,5,8 ). In this case the Minimum value is 1. How to achieve this scenario. (SRPNO = 1001)

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