Palindromic numbers ...

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Ray Dawson

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Feb 24, 2002, 11:00:44 AM2/24/02
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OK, off topic but I have been using Eureka to work it out -
unsuccessfully so far.

My daughter's homework on palindromic numbers states that any two digit
number, when added to its reverse, will make a palindromic number -
although it may need to be done in several stages.

ie

12 17 19 37 68
21 71 91 73 86
33 88 110 110 154
011 011 451
121 121 605
506
1111

You get the idea?

Well, although I produced a large table in Eureka and the above seems to
be so, I've come unstuck on 89. Even though I've got a long column of
figures, and got Eureka well into E numbers, I can't get it to obey the
rules and turn up with a palendromic sum.

Any maths experts tell me what to tell her about 89?

Cheers,

Ray D

--

Ray Dawson
r...@magray.freeserve.co.uk
MagRay - the audio & braille specialists

Dom Wright

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Feb 24, 2002, 11:25:55 AM2/24/02
to
"Ray Dawson" <R...@magray.freeserve.co.uk> wrote in message
news:4b0de2...@magray.freeserve.co.uk...

>
> OK, off topic but I have been using Eureka to work it out -
> unsuccessfully so far.
>
> My daughter's homework on palindromic numbers states that any two digit
> number, when added to its reverse, will make a palindromic number -
> although it may need to be done in several stages.
>
> ie
>
> 12 17 19 37 68
> 21 71 91 73 86
> 33 88 110 110 154
> 011 011 451
> 121 121 605
> 506
> 1111
>
> You get the idea?
>
> Well, although I produced a large table in Eureka and the above seems to
> be so, I've come unstuck on 89. Even though I've got a long column of
> figures, and got Eureka well into E numbers, I can't get it to obey the
> rules and turn up with a palendromic sum.
>
> Any maths experts tell me what to tell her about 89?
>
IMBW,

89
98
187
781
968
869
1837
7381
9218
8129
17347
74371
91688
88619
180307
703081
883388

Tada!

(I hope I didn't get one of those wrnog, I ran out of fingers and toes!)

Dom.


Matthew Somerville

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Feb 24, 2002, 12:35:46 PM2/24/02
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In message <4b0de2...@magray.freeserve.co.uk>
Ray Dawson <R...@magray.freeserve.co.uk> wrote:

> OK, off topic but I have been using Eureka to work it out -
> unsuccessfully so far.

Well, using the RISC OS version of PHP and this program:

--8<-----------
$n = 89; $m = strrev($n);
while ($n != $m) {
$t = $n+$m;
print "$n + $m = $t\n";
$n = $t; $m = strrev($n);
}
--8<-----------

I get:

89 + 98 = 187
187 + 781 = 968
968 + 869 = 1837
1837 + 7381 = 9218
9218 + 8129 = 17347
17347 + 74371 = 91718
91718 + 81719 = 173437
173437 + 734371 = 907808
907808 + 808709 = 1716517
1716517 + 7156171 = 8872688
8872688 + 8862788 = 17735476
17735476 + 67453771 = 85189247
85189247 + 74298158 = 159487405
159487405 + 504784951 = 664272356
664272356 + 653272466 = 1317544822
1317544822 + 2284457131 = 3602001953
3602001953 + 3591002063 = 7193004016
7193004016 + 6104003917 = 13297007933
13297007933 + 33970079231 = 47267087164
47267087164 + 46178076274 = 93445163438
93445163438 + 83436154439 = 176881317877
176881317877 + 778713188671 = 955594506548
955594506548 + 845605495559 = 1801200002107
1801200002107 + 7012000021081 = 8813200023188

Which is palindromic. :)

HTH,
Matthew
--
"Jazz is the sound of the devil sniggering at our follies."
- Edward, My Life So Far

http://www.dracos.co.uk/

Brian Howlett

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Feb 24, 2002, 12:41:09 PM2/24/02
to
On 24 Feb, Dom Wright exclaimed:

> "Ray Dawson" <R...@magray.freeserve.co.uk> wrote in message
> news:4b0de2...@magray.freeserve.co.uk...

[snip]


>> Any maths experts tell me what to tell her about 89?
>>
> IMBW,
>
> 89
> 98
> 187
> 781
> 968
> 869
> 1837
> 7381
> 9218
> 8129
> 17347
> 74371

You slipped up a bit here - 17347 + 74371 = 91718
81719
173437
734371
907808
808709
1716517
7156171
8872688
8862788
17735476
67453771
85189247
74298158
159488505
505884951
665373456
654373566
1329747022
2207479231
3537226253

Doesn't look like I'm getting anywhere near to a solution, and I've got
to go out shortly - I'm sure someone else will be along in a minute with
the rest of the answer...
[snip]


>
> (I hope I didn't get one of those wrnog, I ran out of fingers and
> toes!)
>

You got at least one wrnog ;-)
--
Brian Howlett
--------------------------------
"I'm Brian, and so's my wife..."

Brian Howlett

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Feb 24, 2002, 12:47:23 PM2/24/02
to
On 24 Feb, Brian Howlett exclaimed:

> On 24 Feb, Dom Wright exclaimed:
>

[snip]


>
> Doesn't look like I'm getting anywhere near to a solution, and I've
> got to go out shortly - I'm sure someone else will be along in a
> minute with the rest of the answer... [snip]
>>
>> (I hope I didn't get one of those wrnog, I ran out of fingers and
>> toes!)
>>
> You got at least one wrnog ;-)
>

As did I as can be seen elsewhere on this thread. I will now go and hide
under a rock, and not contribute to any more arithmetic threads...

<mumblemumblearithmeticogradewasyearsagoanywaystupidsumsmumblemumble>
--
Brian Howlett
----------------------------------------------------------------------
"Are you the Prime Minister?" "No, but I've often been mistaken."
"What, for the Prime Minister?" "No. I've just often been mistaken..."

Ken Wright

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Feb 24, 2002, 4:19:38 PM2/24/02
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In article <a5b46i$mrh$1...@knossos.btinternet.com>,

Dom Wright <DomW...@btinternet.com> wrote:
> (I hope I didn't get one of those wrnog, I ran out of fingers and
> toes!)

Do you remember the past-middle-age women in the American sitcom
'The Golden Girls' when talking about some man they knew and one of
the women (I think she was called Dorothy) remarked, "Yes, he was
so dim he had to take off all his clothes before he could count to
twentyone!"

--
__ __ __ __ __ ___ ______________________________________________
|__||__)/ __/ \|\ ||_ | /...Internet access for all Acorn RISC machines
| || \\__/\__/| \||__ | / Ken Wright kcwr...@argonet.co.uk
___________________________/

Ray Dawson

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Feb 24, 2002, 3:33:24 PM2/24/02
to
In article <9ba6eb0d4...@trinity.oxford.ac.uk>,

Matthew Somerville <matthew.s...@trinity.oxford.ac.uk> wrote:
> 47267087164 + 46178076274 = 93445163438

Which is where I got to.

> 93445163438 + 83436154439 = 176881317877
> 176881317877 + 778713188671 = 955594506548
> 955594506548 + 845605495559 = 1801200002107
> 1801200002107 + 7012000021081 = 8813200023188

> Which is palindromic. :)

If only I'd gone on 4 more stages :-)

As the previous longest ones had only 6 stages (79 and 88), I was sure I
had gone wrong at 20 stages with no answer.

ROS402dn

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Feb 24, 2002, 7:17:19 PM2/24/02
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In message <9ba6eb0d4...@trinity.oxford.ac.uk>
Matthew Somerville <matthew.s...@trinity.oxford.ac.uk> wrote:

> In message <4b0de2...@magray.freeserve.co.uk>
> Ray Dawson <R...@magray.freeserve.co.uk> wrote:
>
> > OK, off topic but I have been using Eureka to work it out -
> > unsuccessfully so far.
>
> Well, using the RISC OS version of PHP and this program:
>
> --8<-----------
> $n = 89; $m = strrev($n);
> while ($n != $m) {
> $t = $n+$m;
> print "$n + $m = $t\n";
> $n = $t; $m = strrev($n);
> }
> --8<-----------
>
> I get:
>
> 89 + 98 = 187

[snippy]


> 1801200002107 + 7012000021081 = 8813200023188
>
> Which is palindromic. :)

Or, the mucho simple, runs without any extras, BASIC version ;)

5 REM >PalinNum1
10 IF LEN(STR$(PI/33))<15 THEN PRINT "This program requires the extended accuracy of BASIC64,"'" please load it and try again.":END
30 n=89
40 m=FNrev(n)
50 WHILE n<>m
60 t=n+m
70 PRINT" ";STR$(n);" + ";STR$(m);" = ";STR$(t)
80 n=t
90 m=FNrev(n)
100 ENDWHILE
110 END
120 DEFFNrev(x)
130 LOCAL x$,y$,a%,l%
140 x$=STR$(x)
150 y$=""
160 l%=LENx$
170 FOR a%=0 TO l%-1
180 y$=y$+MID$(x$,l%-a%,1)
190 NEXT
200 =EVAL(y$)

Task window recommended, BASIC64 required.

And here is the solution only version

5 REM >PalinNum2
10 ONERRORREPORT:PRINT" at line ";ERL:END
20 IF LEN(STR$(PI/33))<15 THEN PRINT "This program requires the extended accuracy of BASIC64,"'" please load it and try again.":END
30 FOR b=1 TO 99
40 n=b:m=FNrev(n)
50 PRINT" ";STR$(n);" + ";STR$(m);" = ";
60 REPEAT
70 t=n+m:n=t:m=FNrev(n):UNTILn=m
80 PRINT STR$(t)
90 NEXT
100 END
110 DEFFNrev(x)
120 LOCAL x$,y$,a%,l%
130 x$=STR$(x):y$="":l%=LENx$
140 FORa%=0 TO l%-1
150 y$=y$+MID$(x$,l%-a%,1):NEXT
160 =EVAL(y$)

Change the 99 in line 30 to suit ;)

Darren

Kell Gatherer

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Feb 25, 2002, 5:31:08 AM2/25/02
to
In article <196a10e4b%ne...@sa-rpc-user.fsnet.co.uk>,
ROS402dn <ne...@sa-rpc-user.fsnet.co.uk> wrote:

> Change the 99 in line 30 to suit ;)

It fails at 196.

:-P

--
Kell Gatherer
ke...@locsource.com
The Location Source

Terry Blunt

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Feb 25, 2002, 7:16:45 AM2/25/02
to
In message <4b0e489...@locsource.com>
Kell Gatherer <ke...@locsource.com> wrote:

> In article <196a10e4b%ne...@sa-rpc-user.fsnet.co.uk>,
> ROS402dn <ne...@sa-rpc-user.fsnet.co.uk> wrote:
>
> > Change the 99 in line 30 to suit ;)
>
> It fails at 196.
>
> :-P

Hmmm I dimly remember something in *INFO (I think) where *really* big
numbers were handled as strings in BASIC.

--
Terry Blunt <te...@langri.demon.co.uk>

Sometimes I sits and scratches my head,
but oft times I scratches my bum instead.

Dom Wright

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Feb 25, 2002, 12:15:35 PM2/25/02
to
In the deep and distant past Brian Howlett declared unto the worlds:

> On 24 Feb, Brian Howlett exclaimed:
>
> > On 24 Feb, Dom Wright exclaimed:
> >
> [snip]
> >
> > Doesn't look like I'm getting anywhere near to a solution, and I've
> > got to go out shortly - I'm sure someone else will be along in a
> > minute with the rest of the answer... [snip]
> >>
> >> (I hope I didn't get one of those wrnog, I ran out of fingers and
> >> toes!)
> >>
> > You got at least one wrnog ;-)
> >
> As did I as can be seen elsewhere on this thread. I will now go and hide
> under a rock, and not contribute to any more arithmetic threads...
>
> <mumblemumblearithmeticogradewasyearsagoanywaystupidsumsmumblemumble>

Oh, mumble I'm a programmer, Jim, not a mathematician!

(Goes off to sick-bay to check toe count)

Dom.


Steve Fryatt

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Feb 25, 2002, 3:11:39 PM2/25/02
to
On 25 Feb, in message <a347520e...@langri.demon.co.uk>
Terry Blunt <te...@langri.demon.co.uk> wrote:

> Hmmm I dimly remember something in *INFO (I think) where *really* big
> numbers were handled as strings in BASIC.

Nick Craig-Wood's "Big Numbers" module is (or was) on his website at
http://www.axis.demon.co.uk/. It appeared in AU (I don't think it was in
*Info, but I could be wrong) sometime around 1992 (soon after I started
reading it, which is why I know that..).

--
Steve Fryatt - Glasgow, Scotland

http://www.stevefryatt.org.uk/

Ray Dawson

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Feb 25, 2002, 11:40:41 AM2/25/02
to
> In message <9ba6eb0d4...@trinity.oxford.ac.uk>
> Matthew Somerville <matthew.s...@trinity.oxford.ac.uk> wrote:

> > In message <4b0de2...@magray.freeserve.co.uk>
> > Ray Dawson <R...@magray.freeserve.co.uk> wrote:
> >
> > > OK, off topic but I have been using Eureka to work it out -
> > > unsuccessfully so far.
> >
> > Well, using the RISC OS version of PHP and this program:
> >
> > --8<-----------
> > $n = 89; $m = strrev($n);
> > while ($n != $m) {
> > $t = $n+$m;
> > print "$n + $m = $t\n";
> > $n = $t; $m = strrev($n);
> > }
> > --8<-----------
> >
> > I get:
> >
> > 89 + 98 = 187
> [snippy]
> > 1801200002107 + 7012000021081 = 8813200023188
> >
> > Which is palindromic. :)

> Or, the mucho simple, runs without any extras, BASIC version ;)

> 5 REM >PalinNum1

[snip]

Both these BASIC programs give 'Syntax Error' when run.

Cheers,,

ROS402dn

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Feb 25, 2002, 2:55:42 PM2/25/02
to

> In message <4b0e489...@locsource.com>
> Kell Gatherer <ke...@locsource.com> wrote:
>
> > In article <196a10e4b%ne...@sa-rpc-user.fsnet.co.uk>,
> > ROS402dn <ne...@sa-rpc-user.fsnet.co.uk> wrote:
> >
> > > Change the 99 in line 30 to suit ;)
> >
> > It fails at 196.
> >
> > :-P
>
> Hmmm I dimly remember something in *INFO (I think) where *really* big
> numbers were handled as strings in BASIC.

ISTR seeing a module that effectively gave you BASIC128, but was a 'bit'
of a hack. ;-/

And there is a BASIC library that gives you really big numbers, upto
120 digits IIRC, integer only tho.

ROS402dn

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Feb 25, 2002, 8:42:31 PM2/25/02
to
In message <4b0e6a...@magray.freeserve.co.uk>
Ray Dawson <R...@magray.freeserve.co.uk> wrote:

> In article <196a10e4b%ne...@sa-rpc-user.fsnet.co.uk>,
> ROS402dn <ne...@sa-rpc-user.fsnet.co.uk> wrote:
> > In message <9ba6eb0d4...@trinity.oxford.ac.uk>
> > Matthew Somerville <matthew.s...@trinity.oxford.ac.uk> wrote:
>
> > > In message <4b0de2...@magray.freeserve.co.uk>
> > > Ray Dawson <R...@magray.freeserve.co.uk> wrote:
> > >
> > > > OK, off topic but I have been using Eureka to work it out -
> > > > unsuccessfully so far.
> > >
> > > Well, using the RISC OS version of PHP and this program:
>

> > Or, the mucho simple, runs without any extras, BASIC version ;)
>
> > 5 REM >PalinNum1
>
> [snip]
>
> Both these BASIC programs give 'Syntax Error' when run.

Download and settype as BASIC the two files at
http://www.sa-rpc-user.fsworld.co.uk/palinprogs/


Darren

Michael Curtis

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Feb 25, 2002, 9:42:47 PM2/25/02
to
In message <196a10e4b%ne...@sa-rpc-user.fsnet.co.uk>
ROS402dn <ne...@sa-rpc-user.fsnet.co.uk> wrote:

> In message <9ba6eb0d4...@trinity.oxford.ac.uk>
> Matthew Somerville <matthew.s...@trinity.oxford.ac.uk> wrote:
>
> > Well, using the RISC OS version of PHP and this program:
> >
> > --8<-----------
> > $n = 89; $m = strrev($n);
> > while ($n != $m) {
> > $t = $n+$m;
> > print "$n + $m = $t\n";
> > $n = $t; $m = strrev($n);
> > }
> > --8<-----------
> >
>

> Or, the mucho simple, runs without any extras, BASIC version ;)

What was wrong with the PHP version? Of all the interpreted languages I've
played with (some very briefly), PHP is by far the nicest. One of the
reasons for this is it is so weakly typed. Which is why you can call strrev
on a number. :-)

I think it could be further optimised:

$number = 89; /* choose a start number */
while ($number != ($reverse=strrev($number)))
{
$total = $number + $reverse;
echo $number . ' + ' . $reverse . ' = ' . $total . "\n";
$number = $total;
}

I think it still works...

--
R ### Michael Curtis RISC OS fanatic
I # # Electronics enthusiast
S # #
C # # Software and Acorn Users Waikato :
O ######## http://homepages.ihug.co.nz/~jamjars/
S # MonSetup has suffered a fatal error and must exist immediately

Matthew Somerville

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Feb 26, 2002, 6:41:38 AM2/26/02
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In message <3e91a1e4b%m...@jamjars.localnet>
Michael Curtis <m...@ihug.co.nz> wrote:

> > Or, the mucho simple, runs without any extras, BASIC version ;)
> What was wrong with the PHP version?

I think he was being sarcastic, hency smiley. I hope so, anyway :)

> Of all the interpreted languages I've played with (some very briefly),
> PHP is by far the nicest. One of the reasons for this is it is so
> weakly typed. Which is why you can call strrev on a number. :-)

Good, isn't it? :)

> I think it could be further optimised:

Well, yes, but in the time I would take to optimise something, I could
have written another program and got the results of the first... :)

> $number = 89; /* choose a start number */
> while ($number != ($reverse=strrev($number)))
> {
> $total = $number + $reverse;
> echo $number . ' + ' . $reverse . ' = ' . $total . "\n";
> $number = $total;
> }

Or even further:

$number = 89;
while ($number != ($reverse=strrev($number)))
print "$number + $reverse = ".($number+=$reverse)."\n";

Getting off-topic, anyhoo :)

ATB,
Matthew
--
Martin: I'm a professional killer.
David: Do you have to do post-graduate work for that?

http://www.dracos.co.uk/

Sophie Wilson

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Feb 26, 2002, 5:56:15 AM2/26/02
to
ROS402dn <ne...@sa-rpc-user.fsnet.co.uk> wrote in news:d8c9ce4b%news@sa-rpc-
user.fsnet.co.uk:

You don't need BASIC64 to run these, you just need a better setting of @%
(e.g. to &ff000f0f).

--Sophie

ROS402dn

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Feb 27, 2002, 7:22:22 PM2/27/02
to
In message <Xns91C16F7E0FF23so...@154.32.99.130>
Sophie Wilson <sophie...@bigfoot.com> wrote:

> ROS402dn <ne...@sa-rpc-user.fsnet.co.uk> wrote in
> news:d8c9ce4b%ne...@sa-rpc-user.fsnet.co.uk:


> >
> > Download and settype as BASIC the two files at
> > http://www.sa-rpc-user.fsworld.co.uk/palinprogs/
>
> You don't need BASIC64 to run these, you just need a better setting of @%
> (e.g. to &ff000f0f).

Doing that I get 'Number too big' for PalinNum1, also a rounding error
crops up, same thing happens to PalinNum2.

This is an instance where BASIC64s greater accuracy and longer numbers
is required, at least until n=196 ;)


Darren

Graham Pegg

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Feb 28, 2002, 1:55:28 PM2/28/02
to
In an idle few moments (well, putting off something else I should have
been doing!) I wrote a quickie to use string representations instead
of actual numbers. I stopped it running after n=4000, at which point
it had found over 100 which hadn't achieved palindromicity (?!!!) within
254 digits.

Bit of useless info for you...

Graham
--
+--------------------------------------------------------------------+
| Graham Pegg 'Uncle Greyboots' D...@therpc.fsnet.co.uk |
| Using British Technology: Acorn RiscPC + StrongArm processor |
+--------------------------------------------------------------------+

A clear conscience is usually the result of a bad memory

Tiggr

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Feb 28, 2002, 5:29:58 PM2/28/02
to
In article <e2c87104b%D...@therpc.fsnet.co.uk>,

Graham Pegg <D...@therpc.fsnet.co.uk> wrote:
> In an idle few moments (well, putting off something else I should have
> been doing!) I wrote a quickie to use string representations instead
> of actual numbers. I stopped it running after n=4000, at which point
> it had found over 100 which hadn't achieved palindromicity (?!!!) within
> 254 digits.

> Bit of useless info for you...

As a change from the "the big dictionary" for words a quick look in the
"little dictionary of numbers" [1] reveals the following facts about
pallindromic numbers.

The only number less than 10,000 that has not been proved to produce a
palindrome is 196. (This had been taken (@ 1987) to a number of over
70,000 digits.)

Of the first 100,000 numbers only 5996 have been found not to create a
pallindrome.

In base 2 it is certainly not true that every number generates a
pallindrome, apparently it has been shown that 10110 never does.


Enjoy

Clifford

[1] The Penguin Dictionary of Curious and Interesting Numbers by David
Wells

--
_____
|. _ T...@whitekt.demon.co.uk
||(_)
____) White Knight on the Web - http://www.whitekt.demon.co.uk

Ray Dawson

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Feb 28, 2002, 6:31:03 PM2/28/02
to
In article <d8c9ce4b%ne...@sa-rpc-user.fsnet.co.uk>,

ROS402dn <ne...@sa-rpc-user.fsnet.co.uk> wrote:
> > Both these BASIC programs give 'Syntax Error' when run.

> Download and settype as BASIC the two files at
> http://www.sa-rpc-user.fsworld.co.uk/palinprogs/

Thanks a lot for all the help with palindromic numbers. My daughter was
very pleased - as was her teacher :-)

Cheers,

Andrew Flegg

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Feb 28, 2002, 4:48:14 AM2/28/02
to
Matthew Somerville wrote:
>
> In message <3e91a1e4b%m...@jamjars.localnet>
> Michael Curtis <m...@ihug.co.nz> wrote:
> > Of all the interpreted languages I've played with (some very
> > briefly), PHP is by far the nicest. One of the reasons for this
> > is it is so weakly typed. Which is why you can call strrev on a
> > number. :-)
>
> Good, isn't it? :)

It's just showing its Perl roots, and Perl runs on a whole load more
systems than PHP (including EPOC). To convert the PHP version to
Perl just requires changing 'strrev' to 'reverse':

$n = 89;
print "$n + $r = ".($n += $r)."\n" while $n != ($r = reverse($n));

To get it back on topic, presumably Perl on RISC OS takes less memory
and runs faster than PHP?

Cheers,

Andrew

--
Andrew Flegg -- mailto:and...@bleb.org | http://www.bleb.org/

Matthew Somerville

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Mar 3, 2002, 4:42:14 PM3/3/02
to
In message <3C7DFCDE...@bleb.org>
Andrew Flegg <and...@bleb.org> wrote:

> To get it back on topic, presumably Perl on RISC OS takes less memory
> and runs faster than PHP?

Memory - about the same, I find. Speed - also seems to be the same, but
the major difference between the two is Alex Waugh has released a build
of his web server WebJames with the PHP handler built in -
<http://www.webjames.alexwaugh.com/> - which makes it far faster at
starting up than Perl which has to initialise itself every time it's run.
Also, PHP seems to multitask better than Perl.

I wouldn't try to write Wimp apps in PHP, though - you seem to be able to
with Perl or Python.

ATB,
Matthew
--
"A straight line may be the shortest distance between two points, but it
is by no means the most interesting." - The Doctor, Doctor Who

http://www.dracos.co.uk/

Michael Curtis

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Mar 3, 2002, 9:51:18 PM3/3/02
to
In message <32119d114...@trinity.oxford.ac.uk>
Matthew Somerville <matthew.s...@trinity.oxford.ac.uk> wrote:

> In message <3C7DFCDE...@bleb.org>
> Andrew Flegg <and...@bleb.org> wrote:
>
> > To get it back on topic, presumably Perl on RISC OS takes less memory
> > and runs faster than PHP?
>
> Memory - about the same, I find. Speed - also seems to be the same, but
> the major difference between the two is Alex Waugh has released a build
> of his web server WebJames with the PHP handler built in -
> <http://www.webjames.alexwaugh.com/> - which makes it far faster at
> starting up than Perl which has to initialise itself every time it's run.

I would be surprised if Perl is faster than PHP. PHP 4 is (apparently) one
of the fastest interpreted languages in existence, and can go even faster you
use the optimisation tools from Zend <www.zend.com> (who wrote the core
interpreter).

As for memory, I'd say PHP is bigger because of all the extras that are/can
be compiled into it. This may not be so obvious with the RISC OS version
because it is relatively light on these.

> Also, PHP seems to multitask better than Perl.

Except you must be careful about sending your interpreter into endless loops.
The most common way (for me) is to forgetting to trap that the directory open
command failed, and therefore looping forever because the directory never
ends.

> I wouldn't try to write Wimp apps in PHP, though - you seem to be able to
> with Perl or Python.

(Devils advocate) You can, on the linux version. It's called PHP-GTK+.
See (as always) <www.php.net>.

--
R ### Michael Curtis RISC OS fanatic
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Matthew Somerville

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Mar 5, 2002, 8:57:23 PM3/5/02
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In message <2b5db9114b%m...@jamjars.localnet>
Michael Curtis <m...@ihug.co.nz> wrote:

> > I wouldn't try to write Wimp apps in PHP, though - you seem to be
> > able to with Perl or Python.
> (Devils advocate) You can, on the linux version. It's called
> PHP-GTK+.

That's not exactly useful for creating Wimp apps, though, is it? :) I
mean Perl and Python seem to have Wimp libraries and access to SWI calls,
which PHP does not provide (I'm not saying I want it to, though).

ATB,
Matthew
--
Homer: Don't let Krusty's death get you down, boy. People die all the time,
just like that. Why, you could wake up dead tomorrow.... Well,
goodnight.

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