Re: Dual Buf and Str question
Perhaps https://raku.land/zef:raku-community-modules/Pythonic::Str is what you're after? > On 10 Jun 2022, at 07:54, ToddAndMargo via perl6-users > wrote: > > Hi All, > > I can easily get away with this in Modula2, but > how can I do this with Raku? > > I wish to create a single variable that can be > manipulated in two ways: > > 1) as a fixed length string (Str) > > 2) as a fixed length buffer (Buf) > > I can think of ways to do this, but it would > require separate variable and conversions routines > back and forth. > > Any words of Raku wisdom? > > Many thanks, > -T > > -- > ~~ > Computers are like air conditioners. > They malfunction when you open windows > ~~
Re: Dual Buf and Str question
On 10 Jun 2022, at 07:54, ToddAndMargo via perl6-users wrote: Hi All, I can easily get away with this in Modula2, but how can I do this with Raku? I wish to create a single variable that can be manipulated in two ways: 1) as a fixed length string (Str) 2) as a fixed length buffer (Buf) I can think of ways to do this, but it would require separate variable and conversions routines back and forth. Any words of Raku wisdom? Many thanks, -T On 6/10/22 01:23, Elizabeth Mattijsen wrote: Perhaps https://raku.land/zef:raku-community-modules/Pythonic::Str is what you're after? No really. Maybe if I was to tell you what I am trying to do. I am trying to do a bitwise XOR on each byte against another Buf. Then I want it to act like a string again. I want the variable to act as both an array of characters and a binary array of bytes.
Re: Dual Buf and Str question
> On 10 Jun 2022, at 11:20, ToddAndMargo via perl6-users > wrote: > >>> On 10 Jun 2022, at 07:54, ToddAndMargo via perl6-users >>> wrote: >>> >>> Hi All, >>> >>> I can easily get away with this in Modula2, but >>> how can I do this with Raku? >>> >>> I wish to create a single variable that can be >>> manipulated in two ways: >>> >>> 1) as a fixed length string (Str) >>> >>> 2) as a fixed length buffer (Buf) >>> >>> I can think of ways to do this, but it would >>> require separate variable and conversions routines >>> back and forth. >>> >>> Any words of Raku wisdom? >>> >>> Many thanks, >>> -T > > On 6/10/22 01:23, Elizabeth Mattijsen wrote: >> Perhaps https://raku.land/zef:raku-community-modules/Pythonic::Str is what >> you're after? > > No really. > > Maybe if I was to tell you what I am trying to do. > > I am trying to do a bitwise XOR on each byte > against another Buf. Then I want it to act > like a string again. > > I want the variable to act as both an array > of characters and a binary array of bytes. Convert a string to a Buf: say "abc".encode.Buf; # Buf:0x<61 62 63> Convert a Buf to a Str: say Buf.new(97,98,99).decode; # abc Technically, I think the .encode is enough for what you want: say "abc".encode.does(Blob); # True
Re: Dual Buf and Str question
On 6/10/22 02:36, Elizabeth Mattijsen wrote: On 10 Jun 2022, at 11:20, ToddAndMargo via perl6-users wrote: On 10 Jun 2022, at 07:54, ToddAndMargo via perl6-users wrote: Hi All, I can easily get away with this in Modula2, but how can I do this with Raku? I wish to create a single variable that can be manipulated in two ways: 1) as a fixed length string (Str) 2) as a fixed length buffer (Buf) I can think of ways to do this, but it would require separate variable and conversions routines back and forth. Any words of Raku wisdom? Many thanks, -T On 6/10/22 01:23, Elizabeth Mattijsen wrote: Perhaps https://raku.land/zef:raku-community-modules/Pythonic::Str is what you're after? No really. Maybe if I was to tell you what I am trying to do. I am trying to do a bitwise XOR on each byte against another Buf. Then I want it to act like a string again. I want the variable to act as both an array of characters and a binary array of bytes. Convert a string to a Buf: say "abc".encode.Buf; # Buf:0x<61 62 63> Convert a Buf to a Str: say Buf.new(97,98,99).decode; # abc Technically, I think the .encode is enough for what you want: say "abc".encode.does(Blob); # True I like it. Thank you!
tons of digits
Hi All, I forgot how to write out a ton of digits for the square root of 2 (or any other irrational number). -T -- ~~ Computers are like air conditioners. They malfunction when you open windows ~~
Easier way to load a buffer?
Hi All, I am looking for an easier way to load a buffer. I know about this way [4] > my Buf $b=Buf.new(0x2A, 0x54, 0xFF, 0x53); Buf:0x<2A 54 FF 53> I would like to do it on one big blast: my Buf $b=Buf.new(0x2A54FF53A5F1D36F1CEA7E61FC37A20D54A77FE7B78); Cannot unbox 170 bit wide bigint into native integer But do not know the proper syntax. Any words of wisdom? Am I stuck with the hard way? Many thanks, -T
Re: Easier way to load a buffer?
So Buf is expecting a list of integers. If' you've got one long one in a string like "2A54FF53A5F1D36F1CEA7E61FC37A20D54A77FE7B78" you want to split it into smaller values so something like this? my $hex = "2A54FF53A5F1D36F1CEA7E61FC37A20D54A77FE7B78"; my Buf $b=Buf.new(comb(2).map( *.parse-base(16) )); Which does the trick I think. On Fri, 10 Jun 2022 at 15:49, ToddAndMargo via perl6-users < perl6-us...@perl.org> wrote: > Hi All, > > I am looking for an easier way to load a buffer. > > I know about this way > > [4] > my Buf $b=Buf.new(0x2A, 0x54, 0xFF, 0x53); > Buf:0x<2A 54 FF 53> > > I would like to do it on one big blast: > > my Buf $b=Buf.new(0x2A54FF53A5F1D36F1CEA7E61FC37A20D54A77FE7B78); > Cannot unbox 170 bit wide bigint into native integer > > But do not know the proper syntax. > > Any words of wisdom? Am I stuck with the hard way? > > Many thanks, > -T > -- Simon Proctor Cognoscite aliquid novum cotidie http://www.khanate.co.uk/
Re: Easier way to load a buffer?
On Fri, 10 Jun 2022 at 15:49, ToddAndMargo via perl6-users mailto:perl6-us...@perl.org>> wrote: Hi All, I am looking for an easier way to load a buffer. I know about this way [4] > my Buf $b=Buf.new(0x2A, 0x54, 0xFF, 0x53); Buf:0x<2A 54 FF 53> I would like to do it on one big blast: my Buf $b=Buf.new(0x2A54FF53A5F1D36F1CEA7E61FC37A20D54A77FE7B78); Cannot unbox 170 bit wide bigint into native integer But do not know the proper syntax. Any words of wisdom? Am I stuck with the hard way? Many thanks, -T On 6/10/22 08:36, Simon Proctor wrote: So Buf is expecting a list of integers. If' you've got one long one in a string like "2A54FF53A5F1D36F1CEA7E61FC37A20D54A77FE7B78" you want to split it into smaller values so something like this? my $hex = "2A54FF53A5F1D36F1CEA7E61FC37A20D54A77FE7B78"; my Buf $b=Buf.new(comb(2).map( *.parse-base(16) )); Which does the trick I think. What does the * i *.parse-base do?
Re: Easier way to load a buffer?
> On 10 Jun 2022, at 22:47, ToddAndMargo via perl6-users
> wrote:
>
>>> On Fri, 10 Jun 2022 at 15:49, ToddAndMargo via perl6-users
>>> mailto:perl6-us...@perl.org>> wrote:
>>>Hi All,
>>>I am looking for an easier way to load a buffer.
>>>I know about this way
>>>[4] > my Buf $b=Buf.new(0x2A, 0x54, 0xFF, 0x53);
>>>Buf:0x<2A 54 FF 53>
>>>I would like to do it on one big blast:
>>>my Buf $b=Buf.new(0x2A54FF53A5F1D36F1CEA7E61FC37A20D54A77FE7B78);
>>>Cannot unbox 170 bit wide bigint into native integer
>>>But do not know the proper syntax.
>>>Any words of wisdom? Am I stuck with the hard way?
>>>Many thanks,
>>>-T
>
> On 6/10/22 08:36, Simon Proctor wrote:
>> So Buf is expecting a list of integers. If' you've got one long one in a
>> string like "2A54FF53A5F1D36F1CEA7E61FC37A20D54A77FE7B78" you want to split
>> it into smaller values so something like this?
>> my $hex = "2A54FF53A5F1D36F1CEA7E61FC37A20D54A77FE7B78";
>> my Buf $b=Buf.new(comb(2).map( *.parse-base(16) ));
>> Which does the trick I think.
>
> What does the * i *.parse-base do?
*.parse-base(16) is an example of a WhateverCode object.
It is basically syntactic sugar for easy creation of Callable blocks. In this
case,
it created -> $_ { .parse-base(16) }
The * is interpreted in the Raku Grammar as a sign to create a WhateverCode
object: it basically
represents the $_ in the signature of the created Block, and of course the $_
inside that block.:
Re: Easier way to load a buffer?
On Fri, 10 Jun 2022 at 15:49, ToddAndMargo via perl6-users mailto:perl6-us...@perl.org>> wrote: Hi All, I am looking for an easier way to load a buffer. I know about this way [4] > my Buf $b=Buf.new(0x2A, 0x54, 0xFF, 0x53); Buf:0x<2A 54 FF 53> I would like to do it on one big blast: my Buf $b=Buf.new(0x2A54FF53A5F1D36F1CEA7E61FC37A20D54A77FE7B78); Cannot unbox 170 bit wide bigint into native integer But do not know the proper syntax. Any words of wisdom? Am I stuck with the hard way? Many thanks, -T On 6/10/22 08:36, Simon Proctor wrote: So Buf is expecting a list of integers. If' you've got one long one in a string like "2A54FF53A5F1D36F1CEA7E61FC37A20D54A77FE7B78" you want to split it into smaller values so something like this? my $hex = "2A54FF53A5F1D36F1CEA7E61FC37A20D54A77FE7B78"; my Buf $b=Buf.new(comb(2).map( *.parse-base(16) )); Which does the trick I think. [0] > my $hex = "2A54FF53A5F1D36F1CEA7E61FC37A20D54A77FE7B78"; 2A54FF53A5F1D36F1CEA7E61FC37A20D54A77FE7B78 [1] > my Buf $b=Buf.new(comb(2).map( *.parse-base(16) )); ===SORRY!=== Error while compiling: Calling comb(Int) will never work with signature of the proto ($, $, $?, *%) --> my Buf $b=Buf.new(⏏comb(2).map( *.parse-base(16) )); [1] > -- ~~ Computers are like air conditioners. They malfunction when you open windows ~~
Re: Easier way to load a buffer?
> On 10 Jun 2022, at 23:28, ToddAndMargo via perl6-users > wrote: > >>> On Fri, 10 Jun 2022 at 15:49, ToddAndMargo via perl6-users >>> mailto:perl6-us...@perl.org>> wrote: >>>Hi All, >>>I am looking for an easier way to load a buffer. >>>I know about this way >>>[4] > my Buf $b=Buf.new(0x2A, 0x54, 0xFF, 0x53); >>>Buf:0x<2A 54 FF 53> >>>I would like to do it on one big blast: >>>my Buf $b=Buf.new(0x2A54FF53A5F1D36F1CEA7E61FC37A20D54A77FE7B78); >>>Cannot unbox 170 bit wide bigint into native integer >>>But do not know the proper syntax. >>>Any words of wisdom? Am I stuck with the hard way? >>>Many thanks, >>>-T > > On 6/10/22 08:36, Simon Proctor wrote: >> So Buf is expecting a list of integers. If' you've got one long one in a >> string like "2A54FF53A5F1D36F1CEA7E61FC37A20D54A77FE7B78" you want to split >> it into smaller values so something like this? >> my $hex = "2A54FF53A5F1D36F1CEA7E61FC37A20D54A77FE7B78"; >> my Buf $b=Buf.new(comb(2).map( *.parse-base(16) )); >> Which does the trick I think. > > > [0] > my $hex = "2A54FF53A5F1D36F1CEA7E61FC37A20D54A77FE7B78"; > 2A54FF53A5F1D36F1CEA7E61FC37A20D54A77FE7B78 > [1] > my Buf $b=Buf.new(comb(2).map( *.parse-base(16) )); > ===SORRY!=== Error while compiling: > Calling comb(Int) will never work with signature of the proto ($, $, $?, *%) > --> my Buf $b=Buf.new(⏏comb(2).map( *.parse-base(16) )); > [1] > You could think: what does "comb(2)" do? Perhaps look at the documentation? And then maybe realize that Simon forgot that the comb(2) should be a method on $hex? Otherwise, how would it know what to parse? I know it is hard to think when you're in a hurry. But you should really learn to be able to read code, instead of copying examples only and not understanding *how* they work.
Re: tons of digits
> On Jun 10, 2022, at 8:01 AM, ToddAndMargo via perl6-users
> wrote:
>
> Hi All,
> I forgot how to write out a ton of digits for the square root of 2 (or any
> other irrational number).
Hi Todd,
I suspect that this message is what you have misplaced:
https://www.nntp.perl.org/group/perl.perl6.users/2021/10/msg10221.html
Subject: Re: how do I turn a real into and array of Integers?
In that message, I pointed to an integer_root RosettaCode implementation that,
when used `2` scaled-up by 100²⁰⁰⁰, can easily produce 2000 digits.
Alternately, you can use Math::MPFR from Perl 5 to interface to the GNU MPFR
Library, which has many custom algorithms for crazy-precision irrationals
built-in.
raku -e '
sub precise_square_root ( Numeric $N, UInt $decimal_precision --> Str ) {
use Math::MPFR:from qw<:mpfr>;
my $binary_precision = ceiling( $decimal_precision * log2(10) );
my $bn = Rmpfr_init2($binary_precision);
Rmpfr_set_d($bn, $N , MPFR_RNDN);
Rmpfr_sqrt( $bn, $bn, MPFR_RNDN);
return Rmpfr_get_str($bn, 10, 0, MPFR_RNDN);
}
say precise_square_root(2, 400);
'
Output:
1.41421356237309504880168872420969807856967187537694807317667973799073247846210703885038753432764157273501384623091229702492483605585073721264412149709993583141322266592750559275579995050115278206057147010955997160597027453459686201472851741864088919860955232923048430871432145083976260362799525140798968725339654633180882964062061525835239505474575028775996172983557522033753185701135437460340849884709
--
Hope this helps,
Bruce Gray (Util of PerlMonks)
