++)
{
for(kount=1; kount<=100; kount++)
{
kstep=kstep+1;
time=h*kstep;
k1=h*z;
l1=-h*(bm*z+km*y);
k2=h*(z+l1/2);
l2=-h*(bm*(z+l1/2)+km*(y+k1/2));
k3=h*(z+l2/2);
l3=-h*(bm*(z+l2/2)+km*(y+k2/2));
k4=h*(z+l3);
l4=-h*(bm*(z+13)+km*(y+k3));
y =y+(k1+2*k2+2*k3+k4)/6;
z =z+(l1+2*l2+2*l3+l4)/6;
}
printf("%12.6f %12.5e %12.5e \n", time , y, z);
}
exit(0);
}
Reference
C로 구현한 수치해석,이현일저,
선형회귀분석
#include
#include
double sumX = 0.0, sumXY= 0.0;
double sumY = 0.0, sumXsquare = 0.0;
double xValue[21], yValue[21], xAverage, yAverage, a1,a0;
int i, numberDatepoints;
void main()
{
printf("\n <1> The number of date points : ");
scanf("%d",&numberDatepoints);
printf("\n <2> x값을 입력한 후 comma 찍고 y값을 입력하시오.\n");
for(i=0;i {
printf(" x[%d], y[%d]: ",i+1,i+1);
scanf("%lf,%lf",&(xValue[i]),&(yValue[i]));
}
for(i=0;i {
sumX = sumX + xValue[i];
sumY = sumY + yValue[i];
sumXY = sumXY + xValue[i]*yValue[i];
sumXsquare = sumXsquare + pow(xValue[i],2.0);
}
xAverage = sumX / (numberDatepoints);
yAverage = sumY / (numberDatepoints);
a1=(numberDatepoints*sumXY-sumX*sumY)/(numberDatepoints*sumXsquare-pow(sumX,2.0));
a0=yAverage-a1*xAverage;
printf("\n <3> 입력한 값들에 대한 결과\n");
if(a0==0.0 && a1==0.0)
printf(" y=0 ");
else if(a0==0.0 && a1!=0.0)
printf(" y=%lfx",a1);
else if(a0!=0.0 && a1==0.0)
printf(" y=%lfx",a0);
else
printf(" y=%lf+%lfx",a0,a1);
printf("\n\n\n");
}
결과
선형회귀분석 매틀랩 M_FILE
Matlab Curvefitting Gragh
*Reference
Matlab의 입문과 활용, 김용수저, 높이깊이