81 lines
2.0 KiB
C
81 lines
2.0 KiB
C
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#include "mex.h"
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void mexFunction( int nlhs, mxArray *plhs[],int nrhs, const mxArray*prhs[])
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{
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int mid, m, high, low, i;
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double *position,*hashtable,*hashsearch,hashval;
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hashtable = mxGetPr(prhs[0]);
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hashsearch = mxGetPr(prhs[1]);
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hashval = hashsearch[0];
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plhs[0] = mxCreateDoubleMatrix(1, 1, mxREAL);
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position = mxGetPr(plhs[0]);
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position[0] = 0;
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m = mxGetNumberOfElements(prhs[0]);
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if (m>0)
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{
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low = 0;
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high = m-1;
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i = 0;
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if (hashtable[0] > hashval)
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{
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// No way, the number is smaller than lowest number in table
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position[0] = 0;
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}
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else if (hashtable[high] < hashval)
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{
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position[0] = 0;
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}
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else
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{
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mid = (high+low)/2;
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i = 0;
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while (mid < high & low < mid)
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{
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i++;
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if (i>=2*m)
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{
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//mexPrintf("What!! %i",mid);
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break;
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}
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if (hashtable[mid] < hashval)
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{
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// mexPrintf("Low %i %i %i\n",low,mid,high);
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low = mid;
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}
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else if (hashtable[mid] > hashval)
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{
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// mexPrintf("High %i %i %i\n",low,mid,high);
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high = mid;
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}
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else if (hashtable[mid] == hashval)
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{
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// mexPrintf("Match %i %i %i\n",low,mid,high);
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position[0] = mid+1;
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break;
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}
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mid = (high+low)/2;
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}
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if (hashtable[low] == hashval)
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{
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position[0] = low+1;
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}
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else if (hashtable[high] == hashval)
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{
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position[0] = high+1;
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}
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}
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}
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if (position[0] == 0)
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{
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plhs[0] = mxCreateDoubleMatrix(0, 0, mxREAL);
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}
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}
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