SciCalc

With what? It comes with the OS.

Calc is a much more obvious name for new users than SciCalc!

I agree :) When I originally updated the app I changed the name, but at some point during its adoption it switched back to SciCalc. I’m guessing this is due to licence issues, or possibly because there’s already a !Calc application reserved. It’s not a big issue, but I do think !Calc or !Calculator is a bit friendlier.

So is !SciCalc that is on the current disc build your version that was tested as !Calc 0.74?
Shame it could not be changed to something better. I still just automatically look under C not S for a Calculator…

The version on the current disc build is 0.77 (I think), which has a number of useful fixes over the one I released as 0.74. 0.78, the most recent version in CVS, addresses a glitch with decimal separators in some non-UK territories.

Calc is a much more obvious name for new users than SciCalc!

SciCalc does advertise its features & differenciate from the likes of Apple’s version with only 4 functions.

Using 0.78 to calculate the area of a circle of radius 7, I tried three methods:

1. Enter pi x 7 × 7 = 53.9380401
2. Enter pi x ( 7 x^y 2 ) = 53.93804 (two least significant digits lost)
3. Enter pi x 7 x^y 2 = 483.6106159 (x^y doesn’t take precedence over x) whereas

4. Enter 2 + 6 × 5 = 32 (as in OS 3.6 User Guide p.360, with correct precedence)

Why do cases 1. and 2. differ?

The precedence for case 3. is treated correctly by ROL’s SciCalc 0.67 (25-Mar-2007).

(x^y as the x-to-the-power-of-y button).

In most calculators x or / have higher precedence than + or -, so case 4 is not unexpected.

x and power is likely to have similar precedence so the evaluation proceeds left to right.

1 and 2 differ due to rounding in the two methods?

x and power is likely to have similar precedence so the evaluation proceeds left to right.

Not according to the precedence information in the 0.78 Help file and in the OS 3.6 User Guide p.365.

SciCalc is written in BASIC VI in which ‘^’ has a lower priority than ‘*’. This may not be at all relevant.

Looking only briefly at the two apps, there is one obvious difference in the way they seem to operate in 3. They both calculate a power based on the figure shown in the display, but the ROOL version evalutes previous values before it does so, as if ‘=’ were pressed, whereas the ROL one uses the last entered value. This would account for the anomaly. The difference is also apparent in other functions, such as ‘x root y’ and ‘nPr’ and it would only take a small change in some common code. In 4, ROL and ROOL versions do the same, so other functions must use a different piece of code. If it were worth it I could look for where the difference is.

BODMAS is the mnemonic for the precedence.
Brackets Orders Division Multiplcation Addition Subtraction although division and multiplication are equal priority as are addition and subtraction

If it were worth it I could look for where the difference is.

Thanks Steve D, but it’s Chris (121) who did all the running to provide this (imnproved) ROOL version of SciCalc, and wrote the Help file, so I expect, if he’s willing, he’s the one to check what needs to be altered. How can we ask him? (He’s active in other threads).

This BASIC gives the right answers, 153.93804, on both BASIC and BASIC64.

PRINT  PI * 7 * 7
PRINT  PI * (7^2)
PRINT  PI * 7 ^ 2

SciCalc 0.57 gives the right answer to pi * y ^ 2

My maths teacher went by the nickname of Bod, short for Bodmas, perhaps all maths teachers did.

I’m sure I was taught the ‘O’ in BODMAS stood for ‘OF’. A google reveals some other were taught the same, but I must admit I never really understood what ‘of’ meant in maths. Orders or Exponential is easier to understand I think.

On further reading I now realise I’d been remembering the meaning wrong. From:http://www.channel4.com/programmes/dispatches/articles/2010/kids-dont-count-bodmas

Brackets / Of / Division / Multiplication / Addition / Subtraction.
Unfortunately, this was routinely (and wrongly) recalled [and perhaps taught!] to mean that ‘brackets’ were followed by dealing with the four operations in that order. What it in fact means that brackets are evaluated first, then division and multiplication are to be done before addition and subtraction, but each of these pairs of operations are to be evaluated from left to right.
You can see that 8 – 4 + 3 is wrongly evaluated as 1 by people who have misunderstood BODMAS, failing to get the correct value of 7.

I’d have said 1!

I’d have said 7. In the absence of brackets, and just plus/minus (no precedence), I would parse it left to right.

8 - 4 * 3 is a more interesting question. Is it 12 or -4? Place your bets now. ;-)

You can see that 8 – 4 + 3 is wrongly evaluated as 1 by people who have misunderstood BODMAS, failing to get the correct value of 7.

Left to right, 8-4+3 = (8-4)+3 = 4+3 = 7

8 – 4 * 3 is a more interesting question.

Multiply before subtraction, 8-4*3 = 8-(4*3) = 8-12 = -4

See BODMAS

For me, maybe others:

() – brackets
{} – curly brackets / braces
[] – square brackets
<> – angle brackets (some call them “brockets” which is an affectation I gleefully encourage)
«» – guillemets (French quotes)
「」 – corner brackets (East Asian style quotes)
〔〕 – tortoise shell brackets (aka “because I can”)

;-)

I am surprised nobody has picked me up on this. I said:

SciCalc is written in BASIC VI in which ‘^’ has a lower priority than ‘*’. This may not be at all relevant.

I meant lower priority number, which is a higher evaluation priority, of course. ;-(

As for the naming of those curved things, I had to make an unambiguous choice for the BASIC StrongHelp manual and looked in many places: the OED, HTML tables, other computer languages. So I chose:

However, the BASIC manual refers to () as brackets, so nothing is certain.

So PEMDAS must confuse some?

Quite likely:
An extract from an Oxford publication.
noun (plural parentheses /-siːz/)
1a. word or phrase inserted as an explanation or afterthought into a passage which is grammatically complete without it, in writing usually marked off by brackets, dashes, or commas: in a challenging parenthesis, Wordsworth comments on the evil effects of contemporary developments

(parentheses) a pair of round brackets ( ) used to mark off a parenthetical word or phrase: the stage number is added in parentheses to the name or formula

As Rick pointed out there are multiple types of brackets, so the UK version and the similar Canadian and Australian (using E instead of O to denote Exponent) would apply to those wonderfully obscure calculations that don’t use a round bracket.
PEMDAS or indeed PEDMAS or PEDMSA would work for the simple stuff which is probably the intention.

In short “parenthesis” is the enclosing, the style of enclosure varies.

Perhaps BFODMAS :) .

Sounds like an acronym for the words one says when, in the middle of the night, that obscure and difficult bug still won’t reveal itself, only now the latest code change breaks the compile and one is short on caffeine, even shorter of temper and one is seriously considering jacking it all in and moving to a country that has barely reliable electricity never mind 3G, to do something more productive, like raising sheep.

Or is that just me? ;-)

moving to a country that has barely reliable electricity never mind 3G, to do something more productive, like raising sheep.

Or is that just me? ;-)

Just you. I have a friend, worked for Network Rail, and previous incarnations, for years and now rears sheep.
Still works shifts on the rail and feeds the sheep before the shift and after. Also won’t get ticks since he fell in the sheep dip a little while back – so he tells us on his nice reliable internet connection using his reliable electrical supply.
See – all you had to do was move north to Yorkshire. You just got confused about the direction.

but it’s Chris (121) who did all the running to provide this (imnproved) ROOL version of SciCalc, and wrote the Help file, so I expect, if he’s willing, he’s the one to check what needs to be altered.

How, pray, does one pass my original observation to him while he’s not reading this thread? Perhaps someone knows who he is! (I don’t).

Rick said:

For me, maybe others:

() – brackets

I’ll stop you there. They’re parentheses, not brackets.

{} – curly brackets / braces
[] – square brackets
<> – angle brackets (some call them “brockets” which is an affectation I gleefully encourage)

Nope. They’re the less than and greater than signs. Now if you’d used ⟨ and ⟩ (or for Japanese 〈〉) I’d have agreed.

«» – guillemets (French quotes)

Extra points for spelling it correctly – not the Adobe way!

「」 – corner brackets (East Asian style quotes)
〔〕 – tortoise shell brackets (aka “because I can”)

Actually that’s correct, but don’t forget the lenticular, double angle and ‘white’ corner brackets too: 【】《》『』

As for expression evaluation, the last time I wrote an expression evaluator it had over 40 levels of precedence. It’s not straightforward. (Or at least I managed to contrive it so ;-)

When I updated SciCalc the intention was just to revamp the user interface and leave the internals alone, so I hoped that the actual operation of the calculator was unchanged. However, I did reorganise a lot of the code in order to get the summary bar working, so it looks like something has inadvertently been altered. I’ll take a look at this – it may take a while to find the time, but I’ll do my best!

I think I found the problem might lie in the use of PROCcalc_sum in PROCcalc_binary.

Unfortunately, I found that the !RunImage was in a form without spaces that could not be edited and saved in StrongEd (Zapped maybe?) so I could not go further at that time. Is there an original source here?