32 lines
956 B
C
32 lines
956 B
C
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#include <stdio.h>
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#include <math.h>
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typedef float(*function)(float);
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float rootFindLineSearch(float xl, float xr, float eps, function f)
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{
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float minx = xl, nextstep;
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nextstep = fabs(xr-xl)/(1/eps); //разбиваем на отрезки интервал
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int stepcount=0;
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for(float x=xl; x<xr; x += nextstep, stepcount++)
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{
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if(fabs(f(x)) < fabs(f(minx)))
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minx = x;
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}
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printf("Find Line Search root for %d steps\n",stepcount);
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return minx;
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}
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//(-2, -1.5) (-1.5, -1) (-1, -0.5) (-0.5, 0)
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float f(float x) {
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return 8*x*x*x*x + 32*x*x*x + 40*x*x + 16*x + 1;
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}
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int main() {
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printf("Line Search root1 = %f\n",rootFindLineSearch(-2,-1.5,0.001,f));
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printf("Line Search root2 = %f\n",rootFindLineSearch(-1.5,-1,0.001,f));
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printf("Line Search root3 = %f\n",rootFindLineSearch(-1,-0.5,0.001,f));
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printf("Line Search root4 = %f\n",rootFindLineSearch(-0.5,0, 0.001,f));
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return 0;
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}
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