OpenXM_contrib/pari-2.2/TODO - diff

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Diff for /OpenXM_contrib/pari-2.2/Attic/TODO between version 1.1 and 1.2

version 1.1, 2001/10/02 11:16:55

version 1.2, 2002/09/11 07:26:37

Line 9 Priority classification (first column): [subjective an

3 nice to have

2 maybe not

1 probably not

0 no

- unclassified

*************************** BUGS (general) ****************************

Unless specified otherwise, examples assume 32bit machine and default precision

5 setrand(5);thueinit(x^3 + x^2 - 43690*x - 3529208)

5 bnfinit sometimes gives wrong answers because we cheat on the value of

*** non positive argument in mplog. \\ precision problem

Bach's bound, using 0.3 log^2 D by default, where 0.3 should really be 12

(under GRH). If it's not enough, we compute a subquotient of the classgroup,

i.e junk. Ex:

* setrand(3); bnfinit(y^4 + 1190*y^2 + 1416100).cyc --> [8,2,2,2].

Wrong. The correct structure is [8,4,2].

* setrand(1414185642); bnf = bnfinit(y^4 + 635*y^2 + 403225).reg is twice

the correct value.

5 polgalois(x^8-1864259299553450972214799899167226732549697977945716*x^6+331143259018657601105207922631212331088735421305543663274125986698777318014979969*x^4-2225286541902342283500014249183311190477390*x^2+5);

*** degree too large in tschirn.

4 precision problems in polgalois:

setrand(7);

polgalois(x^8+162644002617632464507038884216211529274267271168000002)

Line 30 Unless specified otherwise, examples assume 32bit mach

Line 41 Unless specified otherwise, examples assume 32bit mach

4 qfbclassno(x < 0) may give a wrong result [e.g x = -2878367]

4 t_SER computations much too slow when number of terms increase, even

when applying a trivial formula, e.g cos(x) at \ps 10000

3 many functions assume MAXVARN is a free variable, yielding bogus

results if the input involve it (only affect library programming).

results if the input involves it (only affects library programming).

3 quadclassunit not reliable when fed non fundamental discriminants

(infinite loop [e.g quadclassunit(-352)], wrong result)

Line 49 Unless specified otherwise, examples assume 32bit mach

Line 57 Unless specified otherwise, examples assume 32bit mach

*************************** BUGS (GP specific) ****************************

5 life of GP variables too short in pathological cases:

5 readline: assume a file 'foo' exists, \rf<TAB> --> \foo [\r f<TAB> is OK]

v = concat(v, [v=1,v=2]); concat(v, [v=1,v=2]) --> SEGV

4 changing primelimit from within forprime loop yields unpredictable results

3 after allocatemem() / default(parisize, ...), the rest of the command is

discarded (ends by a longjmp).

2 under GP after an error, memory is only recovered from "entire variables".

Individual components of lists/vectors/matrices are left alone if the

Line 77 discarded (ends by a longjmp).

Line 84 discarded (ends by a longjmp).

2 HTML version (pod ? SGML ? yodl ???)

*************************** DEVELOPMENT ****************************

*************************** MISCELLANEOUS ****************************

5 write decent (specialized) benches

3 switch to autoconf

3 use stat() instead of opendir() to check if a file is a directory.

*************************** ALGORITHMS ****************************

Kernel:

Line 95 Kernel:

Line 104 Kernel:

4 inline level0 routines should operate on _limbs_, not on words.

3 inline more assembler kernels, alpha in particular (ix86 and sparc are

already inline).

3 FFT for basic types and polynomials (say in A[X], for A = Z, F_q, ...)

2 add support for different multiprecision kernels (a la LiDIA)

Misc:

=====

5 don't assume that nf.zk is HNF. Allow using LLL-T2-reduced bases (with

first element 1) --> huge improvement to all idealred computations (esp.

bnfisprincipal, bnfinit)

4 graphics: allow FIG output (besides PostScript) [easier to edit!]

4 decent finite field package (remove all the nfxxxmodpr functions)

4 rnfkummer (doesn't work)

4 rnfkummer (very slow)

4 nfsubfields [use known subfields to discard blocs right away] (current uses

far too much memory)

4 LLL over R (not stable). Clean up bibli1.c (remove duplicate code)

3 zetak is very inefficient and unable to handle most fields of degree > 8

4 rethink the element_mul type of functions: multiplication table is O(n^3),

polynomial multiplication + remainder is O(n^2) [+ can use Karatsuba/FFT]

3 \ and % (euclidean division) could accept more arguments (e.g t_REAL)

x \ y := floor(x/y) if y > 0 and floor(x/y) + 1 if y < 0

x % y := x - y(x\y) [ hence 0 <= x%y < |y| ]

3 zetak is very inefficient and unable to handle most fields of degree > 6

3 have quadclassunit return bnf structure

3 2-adic initell

3 p-adic ellztopoint

0 graphics: allow FIG output (besides PostScript) [easier to edit!]

[ No: use pstoedit ]

*************************** LIBRARY DESIGN ****************************

4 a system of DEBUGLEVEL classes [e.g \g 5 "LLL" ] (such that the user can

Line 143 Misc:

Line 137 Misc:

4 remove all dependences on types ordering [if (typ(x) < t_POL) ...]

3 integrate Ilya's code for yet bigger prime tables (pari-dev-435). Unify

functions using diffptr (if possible correcting the forprime bug above)

3 remove global variables gpi, geuler: their precision is unpredictable

(at least as much as requested in last const[pi|euler](), possibly much

more). Explicit call to mp[pi|euler] should be required. Will break

Line 174 Misc:

Line 165 Misc:

before all exported functions to prevent name conflicts. Build alias

files for debuggers

2 should use vsnprintf instead of vsprintf in pariputsf. Requires GNU libio.

[paripusf uses static buffer which should be ok for "most" purposes]

*************************** GP DESIGN ****************************

5 remove limitation to 8 arguments for static functions (argvec[9])

4 use divide & conquer approach in string / integer conversions

4 let forprime(n=a, b, ...) work even if a,b above primelimit

4 extend forprime(n=a,b,...) so that b can go over primelimit [cut [a,b]

(maybe with a Warning), via simple sieve + pseudo primality test

in large intervals, sieve out multiple of small primes there, then use

isprime() on the rest]

3 split matrix_block in 2 parts: exploration + assignment. Would allow

Math::Pari to use complicated x[][][][] constructs

3 changevar with explicit (incomplete) permutation. E.g

changevar(p, [x,y], [a,b]) for x -> a, y -> b

add a flag to substitute in succession or in parallel (e.g if a involves y)

Line 208 Misc:

Line 194 Misc:

3 a script to translate "legacy" GP code into something using GP2 function

names

3 write a gp-to-C compiler (adding #defines in anal.c + modifying the

table of functions in init.c, etc, to include the explicit function name).

Should be easy: the code is mostly there.

3 write an analog of the 'echo' default which would print code as it is

executed, not as it is read

2 write a GP scripts debugger (cf above)

2 write a GP scripts debugger

2 write a GP scripts profiler (cf above)

2 write a GP scripts profiler

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