Function createPauliStrSum

quest/src/api/paulis.cpp:166–187

extern "C" PauliStrSum createPauliStrSum(PauliStr* strings, qcomp* coeffs, qindex numTerms) {

    // note we do not require nor impose the strings to be unique
    validate_newPauliStrSumParams(numTerms, __func__);

    // prepare output PauliStrSum (avoiding C++20 designated initialiser)
    PauliStrSum out;
    out.numTerms = numTerms;
    out.strings = cpu_allocPauliStrings(numTerms);                // nullptr if failed
    out.coeffs  = cpu_allocArray(numTerms);                       // nullptr if failed
    out.isApproxHermitian = util_allocEpsilonSensitiveHeapFlag(); // nullptr if failed

    // if either alloc failed, clear both before validation to avoid leak
    freeAllMemoryIfAnyAllocsFailed(out);
    validate_newPauliStrSumAllocs(out, numTerms*sizeof(PauliStr), numTerms*sizeof(qcomp), __func__);

    // otherwise copy given data into new heap structure, and set initial flags
    cpu_copyPauliStrSum(out, strings, coeffs);
    util_setFlagToUnknown(out.isApproxHermitian);

    return out;
}

PauliStrSum createPauliStrSum(vector<PauliStr> strings, vector<qcomp> coeffs) {