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gnn_filewriter.c

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/***************************************************************************
 *  @file gnn_filewriter.c
 *  @brief gnn_filewriter Implementation.
 *
 *  @date   : 28-09-03 18:10
 *  @author : Pedro Ortega C. <peortega@dcc.uchile.cl>
 *  Copyright  2003  Pedro Ortega C.
 ****************************************************************************/
/*
 *  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 Library General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */



/**
 * @defgroup gnn_filewriter_doc gnn_filewriter : File Output Device.
 * @ingroup gnn_output_doc
 * @brief Writes outputs sequentially to a file.
 *
 * The \ref gnn_filewriter implements a sequential file output device. The
 * output patterns are written to a given file stream.
 *
 * This is the datatype for a filewriter. It extends the basic
 * \ref gnn_output structure to include the additional pointer
 * to the output samples matrix, and a vector view.
 *
 * A filewriter, when created, opens the given file in ASCII mode.
 * Alternativelly, you can provide an already opened file pointer. After
 * that, it writes the given samples one after another (line per line) to
 * the opened output stream.
 *
 * By default, vectors are written line-wise, with the format "%g\t" to
 * seperate the elements (of the printed vector). A new format string can
 * be given, of course.
 *
 * Additionally, a prefix and a postfix format string can be used.
 * The are pre- and post-concatenated to the string containing the vector's
 * elements.
 *
 * As an example, the following output will be produced without pre- and
 * postfix strings:
 *
 * \code
 * 12.345   3.45     8
 * 0.1247   3.387    0.001
 * 78.56    5        89.23
 * 12.2356  0.147    0.235
 * \endcode
 *
 * Using the prefix "Pattern %d : [" and postfix "]", the same samples will
 * be printed as:
 *
 * \code
 * Pattern 0 : [12.345   3.45     8 ]
 * Pattern 1 : [0.1247   3.387    0.001 ]
 * Pattern 2 : [78.56    5        89.23 ]
 * Pattern 3 : [12.2356  0.147    0.235 ]
 * \endcode
 *
 * Please note that the prefix contains a "%d" substring. This is the one and
 * only allowed format command for the prefix, which will be replaced by the
 * number of the output sample to be written.
 */



/******************************************/
/* Include Files                          */
/******************************************/

#include <stdio.h>
#include <string.h>
#include "gnn_filewriter.h"



/******************************************/
/* Static Declaration                     */
/******************************************/

/**
 * @brief The datatype for a filewriter.
 * @ingroup gnn_filewriter_doc
 *
 */
typedef struct _gnn_filewriter gnn_filewriter;

struct _gnn_filewriter
{
    gnn_output set;
    FILE *fp;        /*< The output file pointer. */
    int   fileowner; /*< 1 if the \ref gnn_filewriter owns the file. */
    char *format;    /*< The printing format for each vector component. */
    char *prefix;    /*< The prefix. */
    char *postfix;   /*< The postfix. */
};

static int
gnn_filewriter_put (gnn_output *set, size_t k, const gsl_vector *v);

static void
gnn_filewriter_destroy (gnn_output *set);



/******************************************/
/* Static Implementation                  */
/******************************************/

/**
 * @brief The "put" function.
 * @ingroup gnn_filewriter_doc
 *
 * @param  set A pointer to a \ref gnn_filewriter.
 * @param  k   The index of the pattern to be stored.
 * @param  v   A pointer to the output vector to be stored.
 * @return Returns 0 if suceeded.
 */
static int
gnn_filewriter_put (gnn_output *set, size_t k, const gsl_vector *v)
{
    size_t i;
    gnn_filewriter *fset;
    
    /* get view */
    fset = (gnn_filewriter *) set;

    /* print prefix */
    if (fset->prefix)
        fprintf (fset->fp, fset->prefix, k);

    /* printf output vector */
    for (i=0; i<v->size; ++i)
    {
        fprintf (fset->fp, fset->format, gsl_vector_get (v, i));
    }
    
    /* print postfix */
    if (fset->postfix)
        fprintf (fset->fp, fset->prefix, k);

    /* next line */
    fprintf (fset->fp, "\n");

    return 0;
}

/**
 * @brief The "destroy" function.
 * @ingroup gnn_filewriter_doc
 *
 * @param  set A pointer to a \ref gnn_filewriter.
 * @param  k   The index of the pattern to be stored.
 * @param  v   A pointer to the output vector to be stored.
 * @return Returns 0 if suceeded.
 */
static void
gnn_filewriter_destroy (gnn_output *set)
{
    gnn_filewriter *fset;
    
    assert (set != NULL);
    
    fset = (gnn_filewriter *) set;
    
    if (fset->format != NULL)
        free (fset->format);
    if (fset->prefix != NULL)
        free (fset->prefix);
    if (fset->postfix != NULL)
        free (fset->postfix);
    if (fset->fileowner && fset->fp != NULL)
        fclose (fset->fp);
}



/******************************************/
/* Public Interface                       */
/******************************************/

/**
 * @brief Builds a new filewriter device.
 * @ingroup gnn_filewriter_doc
 *
 * This function creates a new \ref gnn_filewriter device with the
 * given opened file pointer. When destroyed, the stream won't be closed.
 *
 * @param  fp A valid and opened file pointer.
 * @return Returns a pointer to a new \ref gnn_filewriter.
 */
gnn_output *
gnn_filewriter_new (FILE *fp)
{
    int status;
    gnn_output *set;
    gnn_filewriter *fset;

    /* check filepointer */
    if (fp == NULL)
    {
        GSL_ERROR_VAL ("a valid file pointer should be given",
                       GSL_EINVAL, NULL);
    }

    /* allocate */
    fset = (gnn_filewriter *) calloc (sizeof (*fset), 1);
    if (fset == NULL)
    {
        GSL_ERROR_VAL ("could not allocate memory for gnn_filewriter",
                       GSL_ENOMEM, NULL);
    }

    /* get view */
    set = (gnn_output *) fset;

    /* initialize */
    status = gnn_output_stream_init (set, NULL,
                                          gnn_filewriter_put,
                                          gnn_filewriter_destroy);
    if (status)
    {
        gnn_output_destroy (set);
        GSL_ERROR_VAL ("could not initialize gnn_filewriter",
                       GSL_EFAILED, NULL);
    }

    /* set fields */
    fset->fp = fp;
    fset->fileowner = 0;
    fset->format  = strdup ("%g\t");
    fset->prefix  = NULL;
    fset->postfix = NULL;

    return set;
}

/**
 * @brief Builds a new filewriter device with a given filename.
 * @ingroup gnn_filewriter_doc
 *
 * This function creates a new \ref gnn_filewriter device. It opens the
 * file \a filename for printing. The \ref gnn_filewriter is the owner of
 * the file and closes it when destroyed.
 *
 * @param  filename A string containing the file name for printing.
 * @return Returns a pointer to a new \ref gnn_filewriter.
 */
gnn_output *
gnn_filewriter_with_file_new (const char *filename)
{
    int status;
    FILE *fp;
    gnn_output *set;
    gnn_filewriter *fset;

    /* check filename */
    if (filename == NULL)
    {
        GSL_ERROR_VAL ("a valid file pointer should be given",
                       GSL_EINVAL, NULL);
    }

    /* open file */
    fp = fopen (filename, "w");
    if (fp == NULL)
    {
        GSL_ERROR_VAL ("couldn't open the given file", GSL_EINVAL, NULL);
    }

    /* create filewriter */
    set = gnn_filewriter_new (fp);

    /* set owner field */
    fset = (gnn_filewriter *) set;
    fset->fileowner = 1;

    return set;
}

/**
 * @brief Sets a new print format.
 * @ingroup gnn_filewriter_doc
 *
 * This function sets a new print format for the vector elements of the
 * samples. The default is \c "%g\t", which separates the elements by tabs.
 * The \em format specifier should contain a valid double-precision
 * specifier, like \c "%f ", \c "%e " or \c "%g " (do not forget to include
 * a separator).
 *
 * @param  set A pointer to a \ref gnn_filewriter.
 * @param  fmt A format string for double precision values.
 * @return Returns a pointer to a new \ref gnn_filewriter.
 */
int
gnn_filewriter_set_format (gnn_output *set, const char *fmt)
{
    gnn_filewriter *fset;

    assert (set != NULL);

    if (fmt == NULL)
    {
        GSL_ERROR ("invalid format string", GSL_EINVAL);
    }

    fset = (gnn_filewriter *) set;

    if (fset->format != NULL)
        free (fset->format);
    fset->format = strdup (fmt);

    return 0;
}

/**
 * @brief Gets the print format.
 * @ingroup gnn_filewriter_doc
 *
 * This function returns a pointer to the currently used vector elements
 * print format.
 *
 * @param  fmt A format string for double precision values.
 * @return Returns a pointer to a new \ref gnn_filewriter.
 */
const char *
gnn_filewriter_get_format (gnn_output *set)
{
    gnn_filewriter *fset;

    assert (set != NULL);

    fset = (gnn_filewriter *) set;

    return fset->format;
}

/**
 * @brief Sets a new printing prefix.
 * @ingroup gnn_filewriter_doc
 *
 * This function sets a new printing prefix, which will be prepended to every
 * printed output vector. This string can contain at most one integer
 * \em format specifier, like \c "N %d :". The placeholder will be filled
 * with the number of the written pattern.
 *
 * @param  set A pointer to a \ref gnn_filewriter.
 * @param  prefix A prefix format string or NULL.
 * @return Returns 0 if succeeded.
 */
int
gnn_filewriter_set_prefix (gnn_output *set, const char *prefix)
{
    gnn_filewriter *fset;

    assert (set != NULL);

    fset = (gnn_filewriter *) set;

    if (fset->prefix != NULL)
        free (fset->prefix);
    fset->prefix = NULL;
    if (prefix != NULL)
        fset->prefix = strdup (prefix);

    return 0;
}

/**
 * @brief Gets the prefix format string.
 * @ingroup gnn_filewriter_doc
 *
 * This function returns a pointer to the currently used prefix string.
 *
 * @param  set A pointer to a \ref gnn_filewriter.
 * @return Returns a pointer to the prefix or NULL.
 */
const char *
gnn_filewriter_get_prefix (gnn_output *set)
{
    gnn_filewriter *fset;

    assert (set != NULL);

    fset = (gnn_filewriter *) set;

    return fset->prefix;
}

/**
 * @brief Sets a new printing postfix.
 * @ingroup gnn_filewriter_doc
 *
 * This function sets a new printing postfix, which will be postpended to every
 * printed output vector. This string can contain at most one integer
 * \em format specifier, like \c "N %d :". The placeholder will be filled
 * with the number of the written pattern.
 *
 * @param  set A pointer to a \ref gnn_filewriter.
 * @param  prefix A postfix format string or NULL.
 * @return Returns 0 if succeeded.
 */
int
gnn_filewriter_set_postfix (gnn_output *set, const char *postfix)
{
    gnn_filewriter *fset;

    assert (set != NULL);

    fset = (gnn_filewriter *) set;

    if (fset->postfix != NULL)
        free (fset->postfix);
    fset->postfix = NULL;
    if (postfix != NULL)
        fset->postfix = strdup (postfix);

    return 0;
}

/**
 * @brief Gets the postfix format string.
 * @ingroup gnn_filewriter_doc
 *
 * This function returns a pointer to the currently used postfix string.
 *
 * @param  set A pointer to a \ref gnn_filewriter.
 * @return Returns a pointer to the postfix or NULL.
 */
const char *
gnn_filewriter_get_postfix (gnn_output *set)
{
    gnn_filewriter *fset;

    assert (set != NULL);

    fset = (gnn_filewriter *) set;

    return fset->postfix;
}


/**
 * @brief Check if it owns the file.
 * @ingroup gnn_filewriter_doc
 *
 * This function returns 1 if the \ref gnn_filewriter owns the file.
 *
 * @param  set A pointer to a \ref gnn_filewriter.
 * @return Returns 1 if it owns the file or 0 if not.
 */
int
gnn_filewriter_owns_file (gnn_output *set)
{
    gnn_filewriter *fset;

    assert (set != NULL);

    fset = (gnn_filewriter *) set;
    if (fset->fileowner)
        return 1;
    else
        return 0;
}

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