gnuplot_i.h
/*-------------------------------------------------------------------------*/
/**
@file gnuplot_i.h
@author N. Devillard
@date Sep 1998
@version $Revision: 1.11 $
@brief C interface to gnuplot.
gnuplot is a freely available, command-driven graphical display tool for
Unix. It compiles and works quite well on a number of Unix flavours as
well as other operating systems. The following module enables sending
display requests to gnuplot through simple C calls.
*/
/*--------------------------------------------------------------------------*/
/*
$Id: gnuplot_i.h,v 1.11 2003/01/27 08:58:04 ndevilla Exp $
$Author: ndevilla $
$Date: 2003/01/27 08:58:04 $
$Revision: 1.11 $
*/
#ifndef _GNUPLOT_PIPES_H_
#define _GNUPLOT_PIPES_H_
/*---------------------------------------------------------------------------
Includes
---------------------------------------------------------------------------*/
#include <stdio.h>
/** Maximal number of simultaneous temporary files */
#define GP_MAX_TMP_FILES 64
/*---------------------------------------------------------------------------
New Types
---------------------------------------------------------------------------*/
/*-------------------------------------------------------------------------*/
/**
@typedef gnuplot_ctrl
@brief gnuplot session handle (opaque type).
This structure holds all necessary information to talk to a gnuplot
session. It is built and returned by gnuplot_init() and later used
by all functions in this module to communicate with the session, then
meant to be closed by gnuplot_close().
This structure is meant to remain opaque, you normally do not need
to know what is contained in there.
*/
/*-------------------------------------------------------------------------*/
typedef struct _GNUPLOT_CTRL_ {
/** Pipe to gnuplot process */
FILE * gnucmd ;
/** Number of currently active plots */
int nplots ;
/** Current plotting style */
char pstyle[32] ;
/** Pointer to table of names of temporary files */
char* tmp_filename_tbl[GP_MAX_TMP_FILES] ;
/** Number of temporary files */
int ntmp ;
} gnuplot_ctrl ;
/*---------------------------------------------------------------------------
Function ANSI C prototypes
---------------------------------------------------------------------------*/
/*-------------------------------------------------------------------------*/
/**
@brief Opens up a gnuplot session, ready to receive commands.
@return Newly allocated gnuplot control structure.
This opens up a new gnuplot session, ready for input. The struct
controlling a gnuplot session should remain opaque and only be
accessed through the provided functions.
The session must be closed using gnuplot_close().
*/
/*--------------------------------------------------------------------------*/
gnuplot_ctrl * gnuplot_init(void);
/*-------------------------------------------------------------------------*/
/**
@brief Closes a gnuplot session previously opened by gnuplot_init()
@param handle Gnuplot session control handle.
@return void
Kills the child PID and deletes all opened temporary files.
It is mandatory to call this function to close the handle, otherwise
temporary files are not cleaned and child process might survive.
*/
/*--------------------------------------------------------------------------*/
void gnuplot_close(gnuplot_ctrl * handle);
/*-------------------------------------------------------------------------*/
/**
@brief Sends a command to an active gnuplot session.
@param handle Gnuplot session control handle
@param cmd Command to send, same as a printf statement.
This sends a string to an active gnuplot session, to be executed.
There is strictly no way to know if the command has been
successfully executed or not.
The command syntax is the same as printf.
Examples:
@code
gnuplot_cmd(g, "plot %d*x", 23.0);
gnuplot_cmd(g, "plot %g * cos(%g * x)", 32.0, -3.0);
@endcode
Since the communication to the gnuplot process is run through
a standard Unix pipe, it is only unidirectional. This means that
it is not possible for this interface to query an error status
back from gnuplot.
*/
/*--------------------------------------------------------------------------*/
void gnuplot_cmd(gnuplot_ctrl * handle, char const * cmd, ...);
/*-------------------------------------------------------------------------*/
/**
@brief Change the plotting style of a gnuplot session.
@param h Gnuplot session control handle
@param plot_style Plotting-style to use (character string)
@return void
The provided plotting style is a character string. It must be one of
the following:
- lines
- points
- linespoints
- impulses
- dots
- steps
- errorbars
- boxes
- boxeserrorbars
*/
/*--------------------------------------------------------------------------*/
void gnuplot_setstyle(gnuplot_ctrl * h, char * plot_style);
/*-------------------------------------------------------------------------*/
/**
@brief Sets the x label of a gnuplot session.
@param h Gnuplot session control handle.
@param label Character string to use for X label.
@return void
Sets the x label for a gnuplot session.
*/
/*--------------------------------------------------------------------------*/
void gnuplot_set_xlabel(gnuplot_ctrl * h, char * label);
/*-------------------------------------------------------------------------*/
/**
@brief Sets the y label of a gnuplot session.
@param h Gnuplot session control handle.
@param label Character string to use for Y label.
@return void
Sets the y label for a gnuplot session.
*/
/*--------------------------------------------------------------------------*/
void gnuplot_set_ylabel(gnuplot_ctrl * h, char * label);
/*-------------------------------------------------------------------------*/
/**
@brief Resets a gnuplot session (next plot will erase previous ones).
@param h Gnuplot session control handle.
@return void
Resets a gnuplot session, i.e. the next plot will erase all previous
ones.
*/
/*--------------------------------------------------------------------------*/
void gnuplot_resetplot(gnuplot_ctrl * h);
/*-------------------------------------------------------------------------*/
/**
@brief Plots a 2d graph from a list of doubles.
@param handle Gnuplot session control handle.
@param d Array of doubles.
@param n Number of values in the passed array.
@param title Title of the plot.
@return void
Plots out a 2d graph from a list of doubles. The x-coordinate is the
index of the double in the list, the y coordinate is the double in
the list.
Example:
@code
gnuplot_ctrl *h ;
double d[50] ;
int i ;
h = gnuplot_init() ;
for (i=0 ; i<50 ; i++) {
d[i] = (double)(i*i) ;
}
gnuplot_plot_x(h, d, 50, "parabola") ;
sleep(2) ;
gnuplot_close(h) ;
@endcode
*/
/*--------------------------------------------------------------------------*/
void gnuplot_plot_x(gnuplot_ctrl * handle, double * d, int n, char * title);
/*-------------------------------------------------------------------------*/
/**
@brief Plot a 2d graph from a list of points.
@param handle Gnuplot session control handle.
@param x Pointer to a list of x coordinates.
@param y Pointer to a list of y coordinates.
@param n Number of doubles in x (assumed the same as in y).
@param title Title of the plot.
@return void
Plots out a 2d graph from a list of points. Provide points through a list
of x and a list of y coordinates. Both provided arrays are assumed to
contain the same number of values.
@code
gnuplot_ctrl *h ;
double x[50] ;
double y[50] ;
int i ;
h = gnuplot_init() ;
for (i=0 ; i<50 ; i++) {
x[i] = (double)(i)/10.0 ;
y[i] = x[i] * x[i] ;
}
gnuplot_plot_xy(h, x, y, 50, "parabola") ;
sleep(2) ;
gnuplot_close(h) ;
@endcode
*/
/*--------------------------------------------------------------------------*/
void gnuplot_plot_xy(
gnuplot_ctrl * handle,
double * x,
double * y,
int n,
char * title
) ;
/*-------------------------------------------------------------------------*/
/**
@brief Open a new session, plot a signal, close the session.
@param title Plot title
@param style Plot style
@param label_x Label for X
@param label_y Label for Y
@param x Array of X coordinates
@param y Array of Y coordinates (can be NULL)
@param n Number of values in x and y.
@return
This function opens a new gnuplot session, plots the provided
signal as an X or XY signal depending on a provided y, waits for
a carriage return on stdin and closes the session.
It is Ok to provide an empty title, empty style, or empty labels for
X and Y. Defaults are provided in this case.
*/
/*--------------------------------------------------------------------------*/
void gnuplot_plot_once(
char * title,
char * style,
char * label_x,
char * label_y,
double * x,
double * y,
int n
);
/*-------------------------------------------------------------------------*/
/**
@brief Plot a slope on a gnuplot session.
@param handle Gnuplot session control handle.
@param a Slope.
@param b Intercept.
@param title Title of the plot.
@return void
Plot a slope on a gnuplot session. The provided slope has an
equation of the form y=ax+b
Example:
@code
gnuplot_ctrl * h ;
double a, b ;
h = gnuplot_init() ;
gnuplot_plot_slope(h, 1.0, 0.0, "unity slope") ;
sleep(2) ;
gnuplot_close(h) ;
@endcode
*/
/*--------------------------------------------------------------------------*/
void gnuplot_plot_slope(
gnuplot_ctrl * handle,
double a,
double b,
char * title
) ;
/*-------------------------------------------------------------------------*/
/**
@brief Plot a curve of given equation y=f(x).
@param h Gnuplot session control handle.
@param equation Equation to plot.
@param title Title of the plot.
@return void
Plots out a curve of given equation. The general form of the
equation is y=f(x), you only provide the f(x) side of the equation.
Example:
@code
gnuplot_ctrl *h ;
char eq[80] ;
h = gnuplot_init() ;
strcpy(eq, "sin(x) * cos(2*x)") ;
gnuplot_plot_equation(h, eq, "sine wave", normal) ;
gnuplot_close(h) ;
@endcode
*/
/*--------------------------------------------------------------------------*/
void gnuplot_plot_equation(gnuplot_ctrl * h, char * equation, char * title) ;
/**
* Writes a CSV file for use with gnuplot commands later. Allows files to also be saved for post
* analysis with excel for example. Arguments are similar to gnuplot_plot_x()
*
* Uses title as gnuplot "comment" on the first line.
*
* @author Peter H Maresh 11/8/2011
*
* @param fileName file name to write to. This should be the same name used in the gnuplot command
* @param d
* @param n
* @param title
* @return int <0 if error writing file.
*
*/
int gnuplot_write_x_csv(
char const * fileName,
double const * d,
int n,
char const * title);
/**
* Writes a CSV file for use with gnuplot commands later. Allows files to also be saved for post
* analysis with excel for example. Arguments are similar to gnuplot_plot_xy()
*
* Uses title as gnuplot "comment" on the first line.
*
* @author Peter H Maresh 11/8/2011
*
* @param fileName file name to write to. This should be the same name used in the gnuplot command
* @param x
* @param y
* @param n
* @param title
* @return int <0 if file wasn't written.
*/
int gnuplot_write_xy_csv(
char const * fileName,
double const * x,
double const * y,
int n,
char const * title);
/**
* Writes a multi column CSV file for use with gnuplot commands later. Allows files to also be
* saved for post analysis with excel for example. Note that when used with gnuplot, since there
* may be more than one column the whole "1:3" or whatever should be used.
*
* Uses title as gnuplot "comment" on the first line.
*
* @author Peter H Maresh 11/8/2011
*
* @param fileName file name to write to. This should be the same name used in the gnuplot
* command
* @param xListPtr A list of pointers to column buffers
* @param n
* @param numColumns Length of xListPtr list. Note that the CSV file will add an additional
* "index" column first.
* @param title Title to write for the first line of the .csv file, will be preceeded by
* "#"
* @return int <0 if file wasn't written.
*/
int gnuplot_write_multi_csv(
char const * fileName,
double const ** xListPtr,
int n,
int numColumns,
char const * title);
#endif
