The R Project SVN R

/*
 *  R : A Computer Language for Statistical Data Analysis
 *  Copyright (C) 1995, 1996  Robert Gentleman and Ross Ihaka
 *  Copyright (C) 1997--2006  Robert Gentleman, Ross Ihaka and the
 *                            R Development Core Team
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, a copy is available at
 *  http://www.r-project.org/Licenses/
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include "Defn.h"

static SEXP cumsum(SEXP x, SEXP s)
{
    int i;
    double sum = 0.0, *rx = REAL(x), *rs = REAL(s);
    for (i = 0 ; i < length(x) ; i++) {
    if (ISNAN(rx[i])) break;
    sum += rx[i];
    rs[i] = sum;
    }
    return s;
}

/* We need to ensure that overflow gives NA here */
static SEXP icumsum(SEXP x, SEXP s)
{
    int i, *ix = INTEGER(x), *is = INTEGER(s);
    double sum = 0.0;
    for (i = 0 ; i < length(x) ; i++) {
    if (ix[i] == NA_INTEGER) break;
    sum += ix[i];
    if(sum > INT_MAX || sum < 1 + INT_MIN) { /* INT_MIN is NA_INTEGER */
        warning(_("Integer overflow in 'cumsum'; use 'cumsum(as.numeric(.))'"));
        break;
    }
    is[i] = sum;
    }
    return s;
}

static SEXP ccumsum(SEXP x, SEXP s)
{
    int i;
    Rcomplex sum;
    sum.r = 0;
    sum.i = 0;
    for (i = 0 ; i < length(x) ; i++) {
    sum.r += COMPLEX(x)[i].r;
    sum.i += COMPLEX(x)[i].i;
    COMPLEX(s)[i].r = sum.r;
    COMPLEX(s)[i].i = sum.i;
    }
    return s;
}

static SEXP cumprod(SEXP x, SEXP s)
{
    int i;
    double prod, *rx = REAL(x), *rs = REAL(s);
    prod = 1.0;
    for (i = 0 ; i < length(x) ; i++) {
    prod *= rx[i];
    rs[i] = prod;
    }
    return s;
}

static SEXP ccumprod(SEXP x, SEXP s)
{
    Rcomplex prod, tmp;
    int i;
    prod.r = 1;
    prod.i = 0;
    for (i = 0 ; i < length(x) ; i++) {
    tmp.r = prod.r;
    tmp.i = prod.i;
    prod.r = COMPLEX(x)[i].r * tmp.r - COMPLEX(x)[i].i * tmp.i;
    prod.i = COMPLEX(x)[i].r * tmp.i + COMPLEX(x)[i].i * tmp.r;
    COMPLEX(s)[i].r = prod.r;
    COMPLEX(s)[i].i = prod.i;
    }
    return s;
}

static SEXP cummax(SEXP x, SEXP s)
{
    int i;
    double max, *rx = REAL(x), *rs = REAL(s);
    max = R_NegInf;
    for (i = 0 ; i < length(x) ; i++) {
    if(ISNAN(rx[i]) || ISNAN(max))
        max = max + rx[i];  /* propagate NA and NaN */
    else
        max = (max > rx[i]) ? max : rx[i];
    rs[i] = max;
    }
    return s;
}

static SEXP cummin(SEXP x, SEXP s)
{
    int i;
    double min, *rx = REAL(x), *rs = REAL(s);
    min = R_PosInf; /* always positive, not NA */
    for (i = 0 ; i < length(x) ; i++ ) {
    if (ISNAN(rx[i]) || ISNAN(min))
        min = min + rx[i];  /* propagate NA and NaN */
    else
        min = (min < rx[i]) ? min : rx[i];
    rs[i] = min;
    }
    return s;
}

static SEXP icummax(SEXP x, SEXP s)
{
    int i, *ix = INTEGER(x), *is = INTEGER(s);
    int max = ix[0];
    is[0] = max;
    for (i = 1 ; i < length(x) ; i++) {
    if(ix[i] == NA_INTEGER) break;
    is[i] = max = (max > ix[i]) ? max : ix[i];
    }
    return s;
}

static SEXP icummin(SEXP x, SEXP s)
{
    int i, *ix = INTEGER(x), *is = INTEGER(s);
    int min = ix[0];
    is[0] = min;
    for (i = 1 ; i < length(x) ; i++ ) {
    if(ix[i] == NA_INTEGER) break;
    is[i] = min = (min < ix[i]) ? min : ix[i];
    }
    return s;
}

SEXP attribute_hidden do_cum(SEXP call, SEXP op, SEXP args, SEXP env)
{
    SEXP s, t, ans;
    int i;
    checkArity(op, args);
    if (DispatchGroup("Math", call, op, args, env, &ans))
    return ans;
    if (isComplex(CAR(args))) {
    t = CAR(args);
    PROTECT(s = allocVector(CPLXSXP, LENGTH(t)));
    setAttrib(s, R_NamesSymbol, getAttrib(t, R_NamesSymbol));
    UNPROTECT(1);
    if(LENGTH(t) == 0) return s;
    for (i = 0 ; i < length(t) ; i++) {
        COMPLEX(s)[i].r = NA_REAL;
        COMPLEX(s)[i].i = NA_REAL;
    }
    switch (PRIMVAL(op) ) {
    case 1: /* cumsum */
        return ccumsum(t, s);
        break;
    case 2: /* cumprod */
        return ccumprod(t, s);
        break;
    case 3: /* cummax */
    case 4: /* cummin */
        errorcall(call, _("min/max not defined for complex numbers"));
        break;
    default:
        errorcall(call, _("unknown cumxxx function"));
    }
    } else if( ( isInteger(CAR(args)) || isLogical(CAR(args)) ) &&
           PRIMVAL(op) != 2) {
    PROTECT(t = coerceVector(CAR(args), INTSXP));
    PROTECT(s = allocVector(INTSXP, LENGTH(t)));
    setAttrib(s, R_NamesSymbol, getAttrib(t, R_NamesSymbol));
    UNPROTECT(2);
    if(LENGTH(t) == 0) return s;
    for(i = 0 ; i < LENGTH(t) ; i++) INTEGER(s)[i] = NA_INTEGER;
    switch (PRIMVAL(op) ) {
    case 1: /* cumsum */
        return icumsum(t,s);
        break;
    case 3: /* cummax */
        return icummax(t,s);
        break;
    case 4: /* cummin */
        return icummin(t,s);
        break;
    default:
        errorcall(call, _("unknown cumxxx function"));
    }
    } else {
    PROTECT(t = coerceVector(CAR(args), REALSXP));
    PROTECT(s = allocVector(REALSXP, LENGTH(t)));
    setAttrib(s, R_NamesSymbol, getAttrib(t, R_NamesSymbol));
    UNPROTECT(2);
    if(LENGTH(t) == 0) return s;
    for(i = 0 ; i < LENGTH(t) ; i++) REAL(s)[i] = NA_REAL;
    switch (PRIMVAL(op) ) {
    case 1: /* cumsum */
        return cumsum(t,s);
        break;
    case 2: /* cumprod */
        return cumprod(t,s);
        break;
    case 3: /* cummax */
        return cummax(t,s);
        break;
    case 4: /* cummin */
        return cummin(t,s);
        break;
    default:
        errorcall(call, _("unknown cumxxx function"));
    }
    }
    return R_NilValue; /* for -Wall */
}