pp_bless('PDL::GSL::INTERP'); # make the functions generated go into our namespace pp_addpm({At=>Top},<<'EOD'); =head1 NAME PDL::GSL::INTERP - PDL interface to Interpolation routines in GSL =head1 DESCRIPTION This is an interface to the interpolation package present in the GNU Scientific Library. =head1 SYNOPSIS use PDL; use PDL::GSL::INTERP; my $x = sequence(10); my $y = exp($x); my $spl = PDL::GSL::INTERP->init('cspline',$x,$y); my $res = $spl->eval(4.35); $res = $spl->deriv(4.35); $res = $spl->deriv2(4.35); $res = $spl->integ(2.1,7.4); =head1 FUNCTIONS =head2 init() =for ref The init method initializes a new instance of INTERP. It needs as input an interpolation type and two piddles holding the x and y values to be interpolated. The GSL routines require that x be monotonically increasing and a quicksort is performed by default to ensure that. You can skip the quicksort by passing the option {Sort => 0}. The available interpolation types are : =over 2 =item linear =item polynomial =item cspline (natural cubic spline) =item cspline_periodic (periodic cubic spline) =item akima (natural akima spline) =item akima_periodic (periodic akima spline) =back Please check the GSL documentation for more information. =for usage Usage: $blessed_ref = PDL::GSL::INTERP->init($interp_method,$x,$y,$opt); =for example Example: $x = sequence(10); $y = exp($x); $spl = PDL::GSL::INTERP->init('cspline',$x,$y) $spl = PDL::GSL::INTERP->init('cspline',$x,$y,{Sort => 1}) #same as above # no sorting done on x, user is certain that x is monotonically increasing $spl = PDL::GSL::INTERP->init('cspline',$x,$y,{Sort => 0}); =head2 eval() =for ref The function eval returns the interpolating function at a given point. By default it will barf if you try to extrapolate, to comply silently if the point to be evaluated is out of range pass the option {Extrapolate => 1} =for usage Usage: $result = $spl->eval($points,$opt); =for example Example: my $res = $spl->eval($x) $res = $spl->eval($x,{Extrapolate => 0}) #same as above # silently comply if $x is out of range $res = $spl->eval($x,{Extrapolate => 1}) =head2 deriv() =for ref The deriv function returns the derivative of the interpolating function at a given point. By default it will barf if you try to extrapolate, to comply silently if the point to be evaluated is out of range pass the option {Extrapolate => 1} =for usage Usage: $result = $spl->deriv($points,$opt); =for example Example: my $res = $spl->deriv($x) $res = $spl->deriv($x,{Extrapolate => 0}) #same as above # silently comply if $x is out of range $res = $spl->deriv($x,{Extrapolate => 1}) =head2 deriv2() =for ref The deriv2 function returns the second derivative of the interpolating function at a given point. By default it will barf if you try to extrapolate, to comply silently if the point to be evaluated is out of range pass the option {Extrapolate => 1} =for usage Usage: $result = $spl->deriv2($points,$opt); =for example Example: my $res = $spl->deriv2($x) $res = $spl->deriv2($x,{Extrapolate => 0}) #same as above # silently comply if $x is out of range $res = $spl->deriv2($x,{Extrapolate => 1}) =head2 integ() =for ref The integ function returns the integral of the interpolating function between two points. By default it will barf if you try to extrapolate, to comply silently if one of the integration limits is out of range pass the option {Extrapolate => 1} =for usage Usage: $result = $spl->integ($a,$b,$opt); =for example Example: my $res = $spl->integ($a,$b) $res = $spl->integ($a,$b,{Extrapolate => 0}) #same as above # silently comply if $a or $b are out of range $res = $spl->eval($a,$b,{Extrapolate => 1}) =head1 BUGS Feedback is welcome. =head1 SEE ALSO L The GSL documentation is online at http://sources.redhat.com/gsl/ref/gsl-ref_toc.html =head1 AUTHOR This file copyright (C) 2003 Andres Jordan All rights reserved. There is no warranty. You are allowed to redistribute this software/documentation under certain conditions. For details, see the file COPYING in the PDL distribution. If this file is separated from the PDL distribution, the copyright notice should be included in the file. The GSL interpolation module was written by Gerard Jungman. =cut EOD pp_addhdr(' #include #include #include #include #include "gslerr.h" typedef gsl_spline GslSpline; typedef gsl_interp_accel GslAccel; '); pp_addpm(' sub init{ my $opt; if (ref($_[$#_]) eq \'HASH\'){ $opt = pop @_; } else{ $opt = {Sort => 1}; } my ($class,$type,$x,$y) = @_; if( (ref($x) ne \'PDL\') || (ref($y) ne \'PDL\') ){ barf("Have to pass piddles as arguments to init method\n"); } if($$opt{Sort} != 0){ my $idx = PDL::Ufunc::qsorti($x); $x = $x->index($idx); $y = $y->index($idx); } my $ene = nelem($x); my $obj1 = new_spline($type,$ene); my $obj2 = new_accel(); init_meat($x,$y,$$obj1); my @ret_a = ($obj1,$obj2); return bless(\@ret_a, $class); } '); pp_def('init_meat', Pars => 'double x(n); double y(n);', OtherPars => 'IV spl', Doc => undef, Code =>' GSLERR(gsl_spline_init,( (gsl_spline *) $COMP(spl), $P(x),$P(y),$SIZE(n)));' ); pp_addpm(' sub eval{ my $opt; if (ref($_[$#_]) eq \'HASH\'){ $opt = pop @_; } else{ $opt = {Extrapolate => 0}; } my ($obj,$x) = @_; my $s_obj = $$obj[0]; my $a_obj = $$obj[1]; if($$opt{Extrapolate} == 0){ return eval_meat($x,$$s_obj,$$a_obj); } else{ return eval_meat_ext($x,$$s_obj,$$a_obj); } } '); pp_def('eval_meat', Pars => 'double x(); double [o] out();', OtherPars => 'IV spl;IV acc;', Doc => undef, # BadCode added 5/31/2005, D. Hunt HandleBad => 1, BadCode => ' if ($ISBAD($x())) { $out() = $x(); } else { GSLERR(gsl_spline_eval_e,( (gsl_spline *) $COMP(spl), $x(), (gsl_interp_accel *) $COMP(acc), $P(out))); } ', Code =>' GSLERR(gsl_spline_eval_e,( (gsl_spline *) $COMP(spl), $x(), (gsl_interp_accel *) $COMP(acc), $P(out))); '); pp_def('eval_meat_ext', Pars => 'double x(); double [o] out();', OtherPars => 'IV spl;IV acc;', Doc => undef, Code =>' $out() = gsl_spline_eval( (gsl_spline *) $COMP(spl), $x(), (gsl_interp_accel *) $COMP(acc)); '); pp_addpm(' sub deriv{ my $opt; if (ref($_[$#_]) eq \'HASH\'){ $opt = pop @_; } else{ $opt = {Extrapolate => 0}; } my ($obj,$x) = @_; my $s_obj = $$obj[0]; my $a_obj = $$obj[1]; if($$opt{Extrapolate} == 0){ return eval_deriv_meat($x,$$s_obj,$$a_obj); } else{ return eval_deriv_meat_ext($x,$$s_obj,$$a_obj); } } '); pp_def('eval_deriv_meat', Pars => 'double x(); double [o] out();', OtherPars => 'IV spl;IV acc;', Doc => undef, Code =>' GSLERR(gsl_spline_eval_deriv_e,( (gsl_spline *) $COMP(spl), $x(), (gsl_interp_accel *) $COMP(acc), $P(out))); '); pp_def('eval_deriv_meat_ext', Pars => 'double x(); double [o] out();', OtherPars => 'IV spl;IV acc;', Doc => undef, Code =>' $out() = gsl_spline_eval_deriv( (gsl_spline *) $COMP(spl), $x(), (gsl_interp_accel *) $COMP(acc)); '); pp_addpm(' sub deriv2{ my $opt; if (ref($_[$#_]) eq \'HASH\'){ $opt = pop @_; } else{ $opt = {Extrapolate => 0}; } my ($obj,$x) = @_; my $s_obj = $$obj[0]; my $a_obj = $$obj[1]; if($$opt{Extrapolate} == 0){ return eval_deriv2_meat($x,$$s_obj,$$a_obj); } else{ return eval_deriv2_meat_ext($x,$$s_obj,$$a_obj); } } '); pp_def('eval_deriv2_meat', Pars => 'double x(); double [o] out();', OtherPars => 'IV spl;IV acc;', Doc => undef, Code =>' GSLERR(gsl_spline_eval_deriv2_e,( (gsl_spline *) $COMP(spl), $x(), (gsl_interp_accel *) $COMP(acc), $P(out))); '); pp_def('eval_deriv2_meat_ext', Pars => 'double x(); double [o] out();', OtherPars => 'IV spl;IV acc;', Doc => undef, Code =>' $out() = gsl_spline_eval_deriv2( (gsl_spline *) $COMP(spl), $x(), (gsl_interp_accel *) $COMP(acc)); '); pp_addpm(' sub integ{ my $opt; if (ref($_[$#_]) eq \'HASH\'){ $opt = pop @_; } else{ $opt = {Extrapolate => 0}; } my ($obj,$a,$b) = @_; my $s_obj = $$obj[0]; my $a_obj = $$obj[1]; if($$opt{Extrapolate} == 0){ return eval_integ_meat($a,$b,$$s_obj,$$a_obj); } else{ return eval_integ_meat_ext($a,$b,$$s_obj,$$a_obj); } } '); pp_def('eval_integ_meat', Pars => 'double a(); double b(); double [o] out();', OtherPars => 'IV spl;IV acc;', Doc => undef, Code =>' GSLERR(gsl_spline_eval_integ_e,( (gsl_spline *) $COMP(spl), $a(), $b(), (gsl_interp_accel *) $COMP(acc),$P(out))); '); pp_def('eval_integ_meat_ext', Pars => 'double a(); double b(); double [o] out();', OtherPars => 'IV spl;IV acc;', Doc => undef, Code =>' $out() = gsl_spline_eval_integ( (gsl_spline *) $COMP(spl), $a(), $b(), (gsl_interp_accel *) $COMP(acc)); '); # XS functions for the INTERP objects pp_addxs('',' MODULE = PDL::GSL::INTERP PACKAGE = PDL::GSL::INTERP #define DEF_INTERP(X) if (!strcmp(TYPE,#X)) spline=gsl_spline_alloc( gsl_interp_ ## X , ene); strcat(ula,#X ", "); GslSpline * new_spline (TYPE,ene) char *TYPE int ene CODE: GslSpline * spline = NULL; char ula[100]; strcpy(ula,""); DEF_INTERP(linear); DEF_INTERP(polynomial); DEF_INTERP(cspline); DEF_INTERP(cspline_periodic); DEF_INTERP(akima); DEF_INTERP(akima_periodic); if (spline==NULL) { barf("Unknown interpolation type, please use one of the following: %s", ula); } else RETVAL = spline; OUTPUT: RETVAL GslAccel * new_accel () CODE: GslAccel * accel = NULL; accel = gsl_interp_accel_alloc(); if (accel == NULL){ barf("Problem allocating accelerator object\n"); } RETVAL = accel; OUTPUT: RETVAL MODULE = PDL::GSL::INTERP PACKAGE = GslSplinePtr PREFIX = spl_ void spl_DESTROY(spline) GslSpline * spline CODE: gsl_spline_free(spline); MODULE = PDL::GSL::INTERP PACKAGE = GslAccelPtr PREFIX = acc_ void acc_DESTROY(accel) GslAccel * accel CODE: gsl_interp_accel_free(accel); '); pp_export_nothing; pp_done();