## Crashing Higher Computing?

### verticalforce

Posted 07 June 2006 - 03:31 PM

Will the programming be too hard for me since everyone else is definitely two years ahead? This is because there are less than 8 students in my account class, so the subject has been cancelled , but it is not definite yet so in the meanwhile the teacher asked me to consider other subjects....

I only have a choice of Modern Studies Higher and Computing and I absolutely hate writing for the Modern Studies....

### st-and Paul

Posted 07 June 2006 - 05:31 PM

### st-and Paul

Posted 07 June 2006 - 05:45 PM

### verticalforce

Posted 07 June 2006 - 05:54 PM

### st-and Paul

Posted 07 June 2006 - 06:56 PM

### John

Posted 08 June 2006 - 06:36 AM

This year the one 5th year i know crashing it in my old school(yay!) is set to get an A or B, along with the rest of the Higher candidates.

The same person also got the highest coursework task mark this year.

So yes its an easy crash.

Also in my opinion there is equal amount of KU to remember in SG and Higher, just additional practical to do, plus a redundant unit(CDP).

### ninja-lewis

Posted 09 June 2006 - 01:15 PM

Although I did have considerable practical knowledge of computing (including stuff more advanced than Higher level), I didn't know much of the theory hence I had to do as much work as everyone else in that area. Similarly, although I had some past experience of coding in HTML/VBscript, I was also a beginner at Java. Provided you get enough practice in class, you should be able to think in code by Christmas so the programming isn't particularly difficult (but finding the mistake that's causing the whole program to crash can be incredibly irritating! )

Provided you've got good resources, a great teacher and don't let yourself be overwhelmed/fall behind, you should be fine.

### verticalforce

Posted 14 June 2006 - 08:16 PM

Binary is awkward.... and confusing at times... (I'm doomed, I found the easiest part of the course hard)

GOT SO MUCH TO LEARN TOO... ARGHHHH....

Starting to regret it here... *quickly reminds himself it will get easier over time with practice*

I also have have to stay back at lunch to catch up in the future... NooooOOooooo...

I'm holding you all responsible if i failed this subject....

PS. Any good Higher books which covers everything in the syllabus? Also, is it necessary for me to purchase SG revision notes, just to see what it is like?

### st-and Paul

Posted 14 June 2006 - 08:32 PM

### verticalforce

Posted 14 June 2006 - 08:40 PM

There are 360 pages (thick), overpriced and was newly published this year.

It must be great, right?

I'm not too keen on programming, binary and all that crap lol, but i must say the course is interesting! I wish we will move on to theory part soon, there's so much about computer that I want to know!

### st-and Paul

Posted 14 June 2006 - 09:49 PM

### verticalforce

Posted 15 June 2006 - 03:27 PM

The teacher never explained this to me..so give me a hand here.

What is signed and magnitude and how do you this? My teacher told me about Least Significant Number but the booklet says Most Significant Number, what the heck? And what about the two's complement?

Let say that you want to find a base 2 from a decimal number of -5. Do you write the number as positive binary, flipped the binaries around and add 1?

And how do you change base2 back to base 10? Do you have to do the same thing, except that you must use subtraction of 1?

Also, i know how to calculate the range from the formula given.... but what does you use it for?

There is also something about exponent & mantissa... again, haven't got a clue about this....

And oh..what do you use ASCII for?

Sorry that i've asked too many questions but i'm completely lost.

### Dave

Posted 15 June 2006 - 04:32 PM

two's complement is used as a better way of representing positive and negative integers. This method means we only have one value for zero. To represent a negative number in two's complement we take the positive value of the number, invert all the bits (ie zero to ones and ones to zeros) then add one to that new number. The result is the negative representation of a number

to go from base 2 to base 10:

this is a pain to try and explain so here we go

in base 10 we have groups of 1's. 10's,100's etc. Which is 10^0,10^1,10^2 etc

so using the same system in base 2 we have groups of 1's.2's,4's etc. Which is 2^0,2^1,2^2

Can you work out 10110 to base 10?

The range of values you can represent is important, as a programmer you need to be able to work out if at any point your program will produce a number which cannot be represented with the word size given. This is known as overflow. Also important in working out the number of bits you need to represent images in a certain color depth

exponent and mantissa is the 2 of 3 things involved in pointing point representation. This is a method of storing real numbers(numbers with a point)

the mantissa holds the numbers involved in the number being stored(if we had 12.4 the mantissa would be 124)

the exponent is the number in places we had to move the point to get a mantissa where everything is to the left of the point(for the example above the exponent would be 1)

the final part of floating point is the base but this is assumed since a computer is a bi-state device

ASCII is the representation for characters. So when type a key on your keyboard a ASCII code is sent from the keyboard to the main tower of the computer

### verticalforce

Posted 15 June 2006 - 06:00 PM

I'm confused since my booklet and you have confirmed by believe of looking at the left side, or the Most Significant Bit but the teacher actually looked at the LSB...

But then again, he told me that 1 is positive until I pointed the book at him.... hmmmmm....

Lets practice: Correct me here, Dave.

Change -5 into binary:

+ve = 0000 0101

invert= 1111 1010

+ (plus) 1

= 1111 1011

Change binary to +ve/-ve number (is it the same step for both?)

= 0000 0101

-(minus) 1

invert= 1111 1011

### Dave

Posted 15 June 2006 - 07:05 PM

The change from binery to +ve/-ve thing i am not sure what you mean

### verticalforce

Posted 15 June 2006 - 08:38 PM

Anyway, how do you change fractional decimal (0.234 for example) to binary and vice versa??

I seriously need to get a book, my school uses the heriott-watt university module and it doesn't seems to explain things in detail.

Do you think i'll be fine? I've only started learning for 2 days. There's a lot more theory that i needed to grasp, it seems that everything in computing correlates to each other.