c34026b101
note: done using ```sh git grep -l "2010-2024 Google" | xargs sed -i 's/2010-2024 Google/2010-2025 Google/' ```
69 lines
2.4 KiB
C++
69 lines
2.4 KiB
C++
// Copyright 2010-2025 Google LLC
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
|
|
#include "ortools/lp_data/lp_print_utils.h"
|
|
|
|
#include <cmath>
|
|
#include <cstdint>
|
|
#include <cstdio>
|
|
#include <limits>
|
|
#include <string>
|
|
|
|
#include "absl/strings/str_cat.h"
|
|
#include "absl/strings/string_view.h"
|
|
#include "ortools/lp_data/lp_types.h"
|
|
#include "ortools/util/rational_approximation.h"
|
|
|
|
namespace operations_research {
|
|
namespace glop {
|
|
|
|
// Returns a string "num/den" representing the rational approximation of x.
|
|
// The absolute difference between the output fraction and the input "x" will
|
|
// not exceed "precision".
|
|
std::string StringifyRational(const double x, const double precision) {
|
|
if (x == kInfinity) {
|
|
return "inf";
|
|
} else if (x == -kInfinity) {
|
|
return "-inf";
|
|
}
|
|
Fraction fraction = RationalApproximation(x, precision);
|
|
const int64_t numerator = fraction.first;
|
|
const int64_t denominator = fraction.second;
|
|
return denominator == 1 ? absl::StrCat(numerator)
|
|
: absl::StrCat(numerator, "/", denominator);
|
|
}
|
|
|
|
std::string Stringify(const Fractional x, bool fraction) {
|
|
return fraction ? StringifyRational(ToDouble(x),
|
|
std::numeric_limits<double>::epsilon())
|
|
: Stringify(x);
|
|
}
|
|
|
|
// Returns a string that pretty-prints a monomial ax with coefficient
|
|
// a and variable name x
|
|
std::string StringifyMonomial(const Fractional a, absl::string_view x,
|
|
bool fraction) {
|
|
if (a == 0.0) return "";
|
|
return a > 0.0
|
|
? absl::StrCat(
|
|
" + ",
|
|
a == 1.0 ? x : absl::StrCat(Stringify(a, fraction), " ", x))
|
|
: absl::StrCat(
|
|
" - ", a == -1.0
|
|
? x
|
|
: absl::StrCat(Stringify(-a, fraction), " ", x));
|
|
}
|
|
|
|
} // namespace glop
|
|
} // namespace operations_research
|