sample4_6.c

本文件是ni公司的labwindows/cvi软件的部分例子和源程序

#include <ansi_c.h>
#include <cvirte.h>    /* Needed if linking in external compiler; harmless otherwise */
#include <userint.h>
#include "sample4_6.h"
#define PI   3.14159   
#define MYEVENT 1000

int panelHandle;
static double waveData[100];


void GenerateSineWave (double amplitude,
                       double cycles, double *waveData);


int main (int argc, char *argv[])
{
    int ControlorMenuID;
    int quit_flag = 1,event;
	double cycles=1,amplitude=5;
	
    if (InitCVIRTE (0, argv, 0) == 0)    /* Needed if linking in external compiler; harmless otherwise */
        return -1;    /* out of memory */
    
    panelHandle = LoadPanel (0, "sample4_6.uir", PANEL);
    DisplayPanel (panelHandle);

    while (quit_flag )
    {
        event=GetUserEvent (0,NULL, &ControlorMenuID);
		if(event==1)
	        switch (ControlorMenuID) 
	        {
	            case PANEL_GENERATESINE:
	                GenerateSineWave (amplitude, cycles, waveData);
	                PlotY (panelHandle, PANEL_GRAPH, waveData, 100, VAL_DOUBLE,
	                       VAL_THIN_LINE, VAL_EMPTY_SQUARE, VAL_SOLID, 1, VAL_RED);
	                break;
	            case PANEL_CYCLES:
					GetCtrlVal (panelHandle, PANEL_CYCLES, &cycles);
					break;
	            case PANEL_AMPLITUDE:
					GetCtrlVal (panelHandle, PANEL_AMPLITUDE, &amplitude);
	            	break;

	            case PANEL_DELETEPLOTS:
	                DeleteGraphPlot (panelHandle, PANEL_GRAPH, -1, 1);
	                break;

	            case PANEL_QUIT:
					QueueUserEvent (MYEVENT, 0, 0);/*quit_flag = 0; */
	            	break;
	        }
	    else if(event>=1000&&event<=10000)
	    	switch (event) 
	    	{
	    		case MYEVENT:
	    			 quit_flag = 0;
	    		break;
	    	}
	}
    DiscardPanel (panelHandle);

    return 0;
} 

void GenerateSineWave (double amplitude,
                       double cycles, double *waveData)
{
    double x, dx;
    int i;
    
    x = 0.0;
    dx = (2.0 * PI) / (double)(100 - 1);
    for (i = 0 ; i < 100 ; i++)
    {
        waveData[i] = sin (cycles * x)*amplitude;
        x += dx;
    }
}