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```EXPORT Ulam
BEGIN
LOCAL a,b,xy:={160,120}, n:=1, m:=.9, d:={{1,0}, {0,1}, {-1,0}, {0,-1}};
RECT();
WHILE n<100000 DO
FOR a FROM 1 TO 4 DO
m:=m+.5;
FOR b FROM 1 TO m DO
IF CAS.isprime(n) THEN PIXON_P(xy,127);END;
xy:=xy+d(a);
n:=n+1;
END;
END;
END;
FREEZE;
END;
//-------------
EXPORT Box(n)
BEGIN
FOR A:=1 TO n DO
RECT_P(FLOOR(RANDOM(320)),FLOOR(RANDOM(260)),FLOOR(RANDOM(320)),FLOOR(RANDOM(260)),0,FLOOR(RANDOM(16581375)));
END;
FREEZE;
END
//-------------------------
LPiece:={100,50,20,10,5,2,1} ;
EXPORT Monnaie(Reste, NPiece)
BEGIN
IF Reste==0 THEN RETURN 1; END;
IF Reste<0 OR NPiece==0 THEN RETURN 0; END;
RETURN Monnaie(Reste-LPiece(NPiece),NPiece)+Monnaie(Reste,NPiece-1);
END;
```

'Ulam' draws the Ulam spiral http://en.wikipedia.org/wiki/Ulam_spiral

'Box(x)' draws x colored box on the screen

'Monnaie' returns the number of ways to get a total. For example Monnaie(100,7) return 4563 : That means there is 4563 ways to get 1 euro (100 cents) with the 7 coins describe in the global variable LPiece

Edited: 22 July 2013, 6:00 p.m.

The program Ulam checks fine, but when I try to run it it says "Ulam Unknowntype"... Do I need to run it in a special way?

Works fine for me...

What happens if you debug ?

You must create a file with the name you want, then copy/paste the code. Then call Ulam from Home view

Edited: 23 July 2013, 2:01 a.m.

That's exactly how I entered it, by copying/pasting from the above post. By the way, this worked fine with Tim's Mandelbrot program.

When I debug, I can step until the IF instruction, then at the next STEP it gives the error message.

then:

The Box program instead works fine.

In old releases 'isprime' was IsPrime or ISPRIME...

Quote:
In old releases 'isprime' was IsPrime or ISPRIME...

and isPrime.

OK, now it doesn't give any error, but it doesn't draw anything - I get a white screen, and after a while, the box of "program finished". Is there some other command that has changed?

On a related note: will we be allowed to check more recent versions of the ROM, with the emulator? It's a little frustrating to find bugs or problems that have been long since solved! :)

Quote:
On a related note: will we be allowed to check more recent versions of the ROM, with the emulator? It's a little frustrating to find bugs or problems that have been long since solved! :)

I agree, it doesn't make much sense to make bugreports for a completely outdated version - that's why I already stopped testing this old HP-Prime 'Prerelease 1'. :-(

Franz

Quote:
Is there some other command that has changed?

Color code...

PIXON_P(xy,127)

try another color code than 127 (0 for example)

Edited: 24 July 2013, 10:54 a.m.

Thanks Gilles, but... still no luck. White screen. I tried with various values.
Maybe I should really just wait for a newer release! :)

I think it's the best ...
I believe it's about the isprime syntax.

isprime(n) may return 1 if true, 0 if false.
it seems it always returns 0 in your program with this release