Operations on a sequence of records

[Felipe Lisboa]

Hi,

My problem is the following:

A have a sequence of many instances of a record. Like this
seq_of_records == <<rec1,rec2,rec3>> 

Where every record has the same type (same fields), but different values for each.

I have to find the minimum value of a certain field between all the instances of that record. Something like:

min_value = min(rec1.a,rec2.a,rec3.a)

I tried:

new_sequence == SelectSeq(seq_of_records, LAMBDA element: element.a)

transform_to_set == ToSet(new_sequence)

min_value = Min(transform_to_set)

But that use of the LAMBDA operator does not seems to be valid. Any tip on how to get just some fields from a sequence of records ?

Thanks

[Stephan Merz]

The second argument of SelectSeq is expected to be a predicate (a Boolean-valued operator). In order to retrieve the set of record fields, simply write

{ seq_of_records[i].a : i \in 1 .. Len(seq_of_records) }

Stephan

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[Felipe Lisboa]

Hi Stephan

Thanks for the answer !

Felipe