[ianking]

30/04/2013 at 12:52 pm

The Subject content notes for Software Desigh and Development mentions positive integers for N4 and just integers for N5 – does this mean that we should be teaching two’s complement at N5 level?

[john]

30/04/2013 at 2:12 pm

I suspect that two’s complement is implied. Hopefully this and many other similar issues will be clarified in the revised content statements that SQA will issue in June.

[chalove]

30/04/2013 at 7:45 pm

That’s a good point John. The new SQA content statements and updated final arrangements will be published in June. We should all remember that what we are working with are the drafts and a number of things will be changing. Not many big changes but clarifications just as you mention.

I’m hoping that we can get rid of some of the inaccurate things that we had previously been teaching and teach the “truth”. Unicode is not just 16-bit for example.

As for Int 2 Integers I think just recognising a negative whole number number being used in a program as an integer would be sufficient.

[tmcguire]

01/05/2013 at 2:07 pm

If we must cover negative numbers I agree with Charlie at Nat 5 an awareness that integers can store negative numbers is enough. (maybe signed-bit but 2’s comp can wait till higher)

We shouldn’t read 2’s comp is implied. We’ve already had people assuming Higher depth knowledge of Buses and Floating point representation among others.

If we continue down that road we’d be in danger of having a course where the majority of content comes from Higher computing and Higher info systems along with the computational thinking. Surely Nat 5 content should be at credit / Int2 level, added challenge and depth can come from code comprehension and algorithm writing.

Re teaching “Truth”. Is that not how science is taught. Start with a simplistic “lie” and as you progress you may disprove that and introduced more truth. The original Unicode standard was 16 bit but it has since evolved. There’s often quite a gulf between enough understanding to grasp the basic theory/concept and understanding complexities of reality to put it into practice.

[Jeremy Scott]

02/05/2013 at 2:18 pm

We interpreted “integers” as meaning two’s complement and have done it with our pupils (we’re doing the course over S3/4). I was quite surprised by how well they got on. However, I also wait on the final arrangements with interest!

[Nicky Pasternak]

19/06/2013 at 2:28 pm

So much for the latest course assessment document in terms of clarifying this issue!

I’d like to re-open this debate.

We are currently debating in school what we need to teach about Integers and Real numbers for SDD at N5.

The latest Course Assessment document states:
The use of binary to represent and store integers and real numbers.

The Specimen question paper q16c asks a question which requires the answer mantissa and exponent despite neither of these being mentioned in the mandatory content.

Do we teach the full current Higher content of floating point representation with examples and then to go onto precision and range?

Similarly with integers, what do we teach? Do we need to teach Two’s complements with examples? If not, then what do we teach about integers?

[Nicky Pasternak]

19/06/2013 at 2:29 pm

So much for the latest course assessment document in terms of clarifying this issue!

I’d like to re-open this debate.

We are currently debating in school what we need to teach about Integers and Real numbers for SDD at N5.

The latest Course Assessment document states:
The use of binary to represent and store integers and real numbers.

The Specimen question paper q16c asks a question which requires the answer mantissa and exponent despite neither of these being mentioned in the mandatory content.

Do we teach the full current Higher content of floating point representation with examples and then to go onto precision and range?

Similarly with integers, what do we teach? Do we need to teach Two’s complements with examples? If not, then what do we teach about integers?