prepare export to pari vector

src/cmd/commands.cpp

@@ -202,6 +202,10 @@ void Commands::minimize(const std::string& path) {
   ProgramUtil::print(program, std::cout);
 }
 
+void throwConversionError(const std::string& format) {
+  throw std::runtime_error("program cannot be converted to " + format);
+}
+
 void Commands::export_(const std::string& path) {
   initLog(true);
   Program program = OeisProgram::getProgramAndSeqId(path).first;
@@ -210,13 +214,19 @@ void Commands::export_(const std::string& path) {
   FormulaGenerator generator;
   if (format.empty() || format == "formula") {
     if (!generator.generate(program, -1, formula, settings.with_deps)) {
-      throw std::runtime_error("program cannot be converted to formula");
+      throwConversionError(format);
     }
     std::cout << formula.toString() << std::endl;
   } else if (format == "pari") {
     if (!generator.generate(program, -1, formula, settings.with_deps) ||
-        !Pari::convertToPari(formula)) {
-      throw std::runtime_error("program cannot be converted to pari");
+        !Pari::convertToPari(formula, false)) {
+      throwConversionError(format);
+    }
+    std::cout << Pari::toString(formula) << std::endl;
+  } else if (format == "pari-vector") {
+    if (!generator.generate(program, -1, formula, settings.with_deps) ||
+        !Pari::convertToPari(formula, true)) {
+      throwConversionError(format);
     }
     std::cout << Pari::toString(formula) << std::endl;
   } else if (format == "loda") {

src/form/pari.cpp

@@ -26,20 +26,10 @@ void convertInitialTermsToIf(Formula& formula) {
   }
 }
 
-void convertFracToPari(Expression& frac) {
-  std::string func = "floor";
-  if (ExpressionUtil::canBeNegative(frac.children.at(0)) ||
-      ExpressionUtil::canBeNegative(frac.children.at(1))) {
-    func = "truncate";
-  }
-  Expression wrapper(Expression::Type::FUNCTION, func, {frac});
-  frac = wrapper;
-}
-
-bool convertExprToPari(Expression& expr) {
+bool convertExprToPari(Expression& expr, const Formula& f, bool as_vector) {
   // convert bottom-up!
   for (auto& c : expr.children) {
-    if (!convertExprToPari(c)) {
+    if (!convertExprToPari(c, f, as_vector)) {
       return false;
     }
   }
@@ -49,6 +39,10 @@ bool convertExprToPari(Expression& expr) {
       return false;
     }
   }
+  if (expr.type == Expression::Type::FUNCTION && as_vector &&
+      f.containsFunctionDef(expr.name)) {
+    expr.type = Expression::Type::VECTOR;
+  }
   return true;
 }
 
@@ -90,12 +84,20 @@ bool addLocalVars(Formula& f) {
   return changed;
 }
 
-bool Pari::convertToPari(Formula& f) {
+bool Pari::convertToPari(Formula& f, bool as_vector) {
+  Formula tmp;
   for (auto& entry : f.entries) {
-    if (!convertExprToPari(entry.second)) {
+    auto left = entry.first;
+    auto right = entry.second;
+    if (as_vector && left.type == Expression::Type::FUNCTION) {
+      left.type = Expression::Type::VECTOR;
+    }
+    if (!convertExprToPari(right, f, as_vector)) {
       return false;
     }
+    tmp.entries[left] = right;
   }
+  f = tmp;
   addLocalVars(f);
   convertInitialTermsToIf(f);
   return true;

src/form/pari.hpp

@@ -16,7 +16,7 @@
  */
 class Pari {
  public:
-  static bool convertToPari(Formula& f);
+  static bool convertToPari(Formula& f, bool as_vector = false);
 
   static std::string toString(const Formula& f);