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M0CNL > TECH 14.06.06 11:14l 155 Lines 7100 Bytes #999 (0) @ WW
BID : 760514M0CNL
Read: DL1LCA GUEST
Subj: Re: GREATC_1.ZIP INFO
Path: DB0FHN<DB0FOR<DB0SIF<DB0FSG<I4UKI<IQ3BV<IZ0AWG<ED1ZAC<GB7YKS<GB7SYP<
GB7ESX<GB7COS
Sent: 060614/0611Z @:GB7COS.#31.GBR.EU #:33257 [Essex, Point Clear] FBB7.00i
From: M0CNL@GB7COS.#31.GBR.EU
To : TECH@WWW
First of all I would like to thank you for receiving my little program so
well, and for your comments both in SP and SB. I would like to make a couple
of comments to the feedback that I received and feel that it better serves
everyone and packet if I make them as an SB rather than SP. I hope you
understand this decision and I am not going to name them as they may not wish
to be named.
First of all it would seem that nobody or at least nobody who has made
themselves known had any problems with it being sent as one part, and the fact
that I have received no .err files it must have made it round the system
intact which goes to show that the packet system we have WORKS and the devoted
SYSOPS we have must be congratulated on that. It would also seem that nobody
had a problem with needing runtime files but as this made use of nothing
special programming wise and the fact that this was programmed in Visual Basic
6 Pro considered by a minority an outdated language and from what I heard by
one programmer today a dinosaur everyone should be using .net a thought that I
think many 100's of thousands of programmers would disagree with, after all
Microsoft claim that it is the language of choice for 90% (can't remember the
exact figure) or even more. Sorry for my ramblings/rantings there, back to the
subject.
In no particular order:
>"No problem here using Win XP Home Edition SP2."
It has been tested on
95 95b 98 98SE
ME (ME is the spawn of Satan IMHO)
2000 AS and pro
and XP pro not home but I didn't expect any problems there
So thanks for that it means it should run on anything 95 or above
>"A nice little program."
Well I am glad you think so, I do too, it was my firstborn now out in the big
bad world to fend for its self.........
>"ahh what a refreshing choice of font"
Wasn't sure on this one but I hope what was meant from it was that my choice
was a good one, Clean, A good size and easy to read, because that is what I
thought when I chose it, can't remember what it was as I don't have access to
the development machine right at this moment.
>"I like the FRABRA image!"
So do/did I it came about playing with a new SSTV program that was able to
give quite nice effects to text and this "logo" kind of came out of that.
>"I did rename the exe to GcCalc.exe for ease of use, hope you don't
> mind? Ir runs like a dream in Win98SE and no complaints of missing .dll
> files or anything else. It now resides permanently in my D:\Radio\Misc
> folder."
I do not mind that at all, I am glad that it worked well for you, and honored
that you consider it worthy of your precious disk space.
As a side note the only things that I would not like is for it to be
disassembled (no effort has been made to hide the code) or to be put on any
website/FTP or published or sold as it is only a BETA version, Once a final
version come out then maybe my stance on that may change.
>"I did a calculation from my QTH to a QTH in Portugal and it said the distance >is 987.3099 miles. I
then used the GreatCir prog by ***** and it gave a >distance of 935 miles. A
rather larger discrepancy than about 5% you mentioned >in your bulletin.
Nevertheless, quite a nice simple little program."
***** (REMOVED AS THEY ARE NOT HERE TO GIVE THEIR SIDE OF THE STORY)
This one I must admit had me a little worried as to how my program could give
such a different result to another such program. As I said earlier I don't
have access to the development machine right now, and added to that I cannot
find the notes for the calculation used and the figure used for the average
circumference of the earth, it has made this difficult to address. So what I
did was some research into great circle distance calculation and could only
find one worked example, which would hopefully shed some light on the error.
The example I found was on the internet so I will show the link here as then
anyone can verify the answer with any other program they have as well.
http://en.wikipedia.org/wiki/Great_circle_distance
They seem to say the same as I did as to the figure taken for the
circumference of the earth and go into much more detail as to why and suggest
an accepted value. They also give example formulae of varying complexity with
some quite heady explanations of them. But they give a worked example !
>"Nashville International Airport (BNA) in Nashville,TN USA:
>N 36ø7.2',W 86ø40.2'
>Los Angeles International Airport (LAX) in Los Angeles,CA USA:
>N 33ø56.4',W 118ø24.0'
>
>Which gives an answer of:
>
>2887.259km 1794miles" (the figure for miles is rounded so we will ignore it)
They state that the figure used for the earths radius results in an error of
up to about 0.5%
Using my Program I get the results:
2886.568km 1792.683miles
So you see my value for km is 99.97606% accurate to theirs which implies my
program functions better than I expected. either that or we are both way off,
both of which is possible.
The problem with comparing programs of this type is that we don't always know
what formula was used and its accuracy, the figure used for the circumference
of the earth and the inherent inaccuracy of what is used as an average figure.
And by comparing the two figures you are compounding the inherent errors of
the programs.
Take for example as a worst case scenario mine gives an error of say +5% and
the other has an error of -5% you are now in the realms of an inaccuracy of
10%
an error that is easily covered by the difference you found.
In conclusion I am not going to assume that mine is right or wrong just as I
am not going to say the other program is right or wrong, just that there is an
error somewhere.
PLEASE DON'T TAKE ANY OF THIS AS ANYTHING OTHER THAN A CHANCE TO WORK OVER THE
GREY MATTER AND AN OPPOTUNITY TO HAVE AN OPEN DISCUSSION
And lastly on a lighter note one final comment received:
"At 70 years old I envy you your programming skills."
Don't let that stop you! the person who started me off in Visual Basic
programming was a little older than yourself. He was given a computer by his
son who couldn't get on with it, and that computer had a few programs left on
it when he got it. I went to his house one day to fix a problem he was having
and he asked me what this Visual Basic was, so I told him and thought nothing
more of it. Several months or so later I had occasion to visit him again and
he was proud to show me what he had achieved using Visual Basic in the last
few months needless to say he had produced several nice little programs. A few
weeks later thinking about this I thought well if he can do it so can I, and
several years later I don't really class myself as having any programming
skills its more a case of I can muddle through. So give it a go you have
nothing to lose except more time spent (wasted as the xyl puts it) enjoying
yourself in the shack.
Thank you to those of you whose comments didn't make it here, but this bull is
far too long as it is. If anyone does wish to send me any more comments I am
only to happy to receive them.
All The Best
Paul
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