* - ^(*(x,y,z),c) -> *(x^c,y^c,z^c) (if c integer)
* - ^(*(x,c1),c2) -> ^(x,c2)*c1^c2 (c1>0)
* - ^(*(x,c1),c2) -> ^(-x,c2)*c1^c2 (c1<0)
- *
- * @param level cut-off in recursive evaluation */
-ex power::eval(int level) const
+ */
+ex power::eval() const
{
- if ((level==1) && (flags & status_flags::evaluated))
+ if (flags & status_flags::evaluated)
return *this;
- else if (level == -max_recursion_level)
- throw(std::runtime_error("max recursion level reached"));
-
- const ex & ebasis = level==1 ? basis : basis.eval(level-1);
- const ex & eexponent = level==1 ? exponent : exponent.eval(level-1);
-
+
const numeric *num_basis = nullptr;
const numeric *num_exponent = nullptr;
-
- if (is_exactly_a<numeric>(ebasis)) {
- num_basis = &ex_to<numeric>(ebasis);
+
+ if (is_exactly_a<numeric>(basis)) {
+ num_basis = &ex_to<numeric>(basis);
}
- if (is_exactly_a<numeric>(eexponent)) {
- num_exponent = &ex_to<numeric>(eexponent);
+ if (is_exactly_a<numeric>(exponent)) {
+ num_exponent = &ex_to<numeric>(exponent);
}
// ^(x,0) -> 1 (0^0 also handled here)
- if (eexponent.is_zero()) {
- if (ebasis.is_zero())
+ if (exponent.is_zero()) {
+ if (basis.is_zero())
throw (std::domain_error("power::eval(): pow(0,0) is undefined"));
else
return _ex1;
}
// ^(x,1) -> x
- if (eexponent.is_equal(_ex1))
- return ebasis;
+ if (exponent.is_equal(_ex1))
+ return basis;
// ^(0,c1) -> 0 or exception (depending on real value of c1)
- if ( ebasis.is_zero() && num_exponent ) {
+ if (basis.is_zero() && num_exponent) {
if ((num_exponent->real()).is_zero())
throw (std::domain_error("power::eval(): pow(0,I) is undefined"));
else if ((num_exponent->real()).is_negative())
}
// ^(1,x) -> 1
- if (ebasis.is_equal(_ex1))
+ if (basis.is_equal(_ex1))
return _ex1;
// power of a function calculated by separate rules defined for this function
- if (is_exactly_a<function>(ebasis))
- return ex_to<function>(ebasis).power(eexponent);
+ if (is_exactly_a<function>(basis))
+ return ex_to<function>(basis).power(exponent);
// Turn (x^c)^d into x^(c*d) in the case that x is positive and c is real.
- if (is_exactly_a<power>(ebasis) && ebasis.op(0).info(info_flags::positive) && ebasis.op(1).info(info_flags::real))
- return power(ebasis.op(0), ebasis.op(1) * eexponent);
+ if (is_exactly_a<power>(basis) && basis.op(0).info(info_flags::positive) && basis.op(1).info(info_flags::real))
+ return power(basis.op(0), basis.op(1) * exponent);
if ( num_exponent ) {
// ^(^(x,c1),c2) -> ^(x,c1*c2)
// (c1, c2 numeric(), c2 integer or -1 < c1 <= 1 or (c1=-1 and c2>0),
// case c1==1 should not happen, see below!)
- if (is_exactly_a<power>(ebasis)) {
- const power & sub_power = ex_to<power>(ebasis);
+ if (is_exactly_a<power>(basis)) {
+ const power & sub_power = ex_to<power>(basis);
const ex & sub_basis = sub_power.basis;
const ex & sub_exponent = sub_power.exponent;
if (is_exactly_a<numeric>(sub_exponent)) {
}
// ^(*(x,y,z),c1) -> *(x^c1,y^c1,z^c1) (c1 integer)
- if (num_exponent->is_integer() && is_exactly_a<mul>(ebasis)) {
- return expand_mul(ex_to<mul>(ebasis), *num_exponent, 0);
+ if (num_exponent->is_integer() && is_exactly_a<mul>(basis)) {
+ return expand_mul(ex_to<mul>(basis), *num_exponent, 0);
}
// (2*x + 6*y)^(-4) -> 1/16*(x + 3*y)^(-4)
- if (num_exponent->is_integer() && is_exactly_a<add>(ebasis)) {
- numeric icont = ebasis.integer_content();
+ if (num_exponent->is_integer() && is_exactly_a<add>(basis)) {
+ numeric icont = basis.integer_content();
const numeric lead_coeff =
- ex_to<numeric>(ex_to<add>(ebasis).seq.begin()->coeff).div(icont);
+ ex_to<numeric>(ex_to<add>(basis).seq.begin()->coeff).div(icont);
const bool canonicalizable = lead_coeff.is_integer();
const bool unit_normal = lead_coeff.is_pos_integer();
icont = icont.mul(*_num_1_p);
if (canonicalizable && (icont != *_num1_p)) {
- const add& addref = ex_to<add>(ebasis);
+ const add& addref = ex_to<add>(basis);
add & addp = dynallocate<add>(addref);
addp.clearflag(status_flags::hash_calculated);
addp.overall_coeff = ex_to<numeric>(addp.overall_coeff).div_dyn(icont);
// ^(*(...,x;c1),c2) -> *(^(*(...,x;1),c2),c1^c2) (c1, c2 numeric(), c1>0)
// ^(*(...,x;c1),c2) -> *(^(*(...,x;-1),c2),(-c1)^c2) (c1, c2 numeric(), c1<0)
- if (is_exactly_a<mul>(ebasis)) {
+ if (is_exactly_a<mul>(basis)) {
GINAC_ASSERT(!num_exponent->is_integer()); // should have been handled above
- const mul & mulref = ex_to<mul>(ebasis);
+ const mul & mulref = ex_to<mul>(basis);
if (!mulref.overall_coeff.is_equal(_ex1)) {
const numeric & num_coeff = ex_to<numeric>(mulref.overall_coeff);
if (num_coeff.is_real()) {
// ^(nc,c1) -> ncmul(nc,nc,...) (c1 positive integer, unless nc is a matrix)
if (num_exponent->is_pos_integer() &&
- ebasis.return_type() != return_types::commutative &&
- !is_a<matrix>(ebasis)) {
- return ncmul(exvector(num_exponent->to_int(), ebasis));
+ basis.return_type() != return_types::commutative &&
+ !is_a<matrix>(basis)) {
+ return ncmul(exvector(num_exponent->to_int(), basis));
}
}
-
- if (are_ex_trivially_equal(ebasis,basis) &&
- are_ex_trivially_equal(eexponent,exponent)) {
- return this->hold();
- }
- return dynallocate<power>(ebasis, eexponent).setflag(status_flags::evaluated);
+
+ return this->hold();
}
ex power::evalf(int level) const
git://www.ginac.de / ginac.git / blobdiff