mirror of https://github.com/BOINC/boinc.git
40 lines
911 B
C++
40 lines
911 B
C++
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// fermi.cpp -- core calculation of Rappture example app-fermi
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#include <stdlib.h>
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#include <stdio.h>
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#include <math.h>
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#include <unistd.h>
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int main(int argc, char * argv[]) {
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double T, Ef, E, dE, kT, Emin, Emax, f;
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FILE *fo = fopen("fermi_out.dat", "w");
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if (!fo) {
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fprintf(stderr, "Failed to open output file\n");
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exit(-1);
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}
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// Check args
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if (3 != argc) {
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fprintf(stderr, "Usage: %s T Ef\n", argv[0]);
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exit(-1);
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}
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T = atof(argv[1]); // in K
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Ef = atof(argv[2]); // in eV
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kT = 8.61734e-5 * T;
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Emin = Ef - 10.0*kT;
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Emax = Ef + 10.0*kT;
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E = Emin;
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dE = 0.005*(Emax-Emin);
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while (E < Emax) {
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f = 1.0/(1.0 + exp((E - Ef)/kT));
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fprintf(fo, "%f %f\n",f, E);
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fprintf(stdout, "=RAPPTURE-PROGRESS=>%d\n", (int)((E-Emin)/(Emax-Emin)*100));
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E = E + dE;
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}
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fclose(fo);
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return 0;
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}
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