Place calculus operator priority between addition/subtraction and mutiplication/division in Latexise (#656)

Author: Happypig375

Sources/AngouriMath/Core/Entity/Continuous/Entity.Continuous.Calculus.Classes.cs

@@ -16,7 +16,7 @@ partial record Entity
         /// <summary>
         /// A node of derivative
         /// </summary>
-        public sealed partial record Derivativef(Entity Expression, Entity Var, int Iterations) : Function
+        public sealed partial record Derivativef(Entity Expression, Entity Var, int Iterations) : CalculusOperator(Expression, Var)
         {
             /// <summary>Reuse the cache by returning the same object if possible</summary>
             private Derivativef New(Entity expression, Entity var) =>
@@ -32,7 +32,7 @@ public override Entity Replace(Func<Entity, Entity> func) =>
         /// <summary>
         /// A node of integral
         /// </summary>
-        public sealed partial record Integralf(Entity Expression, Entity Var, int Iterations) : Function
+        public sealed partial record Integralf(Entity Expression, Entity Var, int Iterations) : CalculusOperator(Expression, Var)
         {
             /// <summary>Reuse the cache by returning the same object if possible</summary>
             private Integralf New(Entity expression, Entity var) =>
@@ -48,7 +48,7 @@ public override Entity Replace(Func<Entity, Entity> func) =>
         /// <summary>
         /// A node of limit
         /// </summary>
-        public sealed partial record Limitf(Entity Expression, Entity Var, Entity Destination, ApproachFrom ApproachFrom) : Function
+        public sealed partial record Limitf(Entity Expression, Entity Var, Entity Destination, ApproachFrom ApproachFrom) : CalculusOperator(Expression, Var)
         {
             /// <summary>Reuse the cache by returning the same object if possible</summary>
             private Limitf New(Entity expression, Entity var, Entity destination, ApproachFrom approachFrom) =>

Sources/AngouriMath/Core/Entity/Continuous/Entity.Continuous.Definition.cs

@@ -17,12 +17,27 @@ public abstract partial record ContinuousNode : Entity
 
         }
 
+        /// <summary>
+        /// Describes any node that is a function (e. g. sin, cos, etc.) or calculus operator (e. g. derivative, integral, limit)
+        /// but not an arithmetic operator or leaf
+        /// </summary>
+        public abstract record Function : ContinuousNode
+        {
+            internal override Priority Priority => Priority.Func;
+        }
+
         /// <summary>
         /// Describes any function that is related to trigonometry
         /// </summary>
         public abstract record TrigonometricFunction : Function
         {
 
+        }
+        /// <summary>
+        /// Describes any calculus operator
+        /// </summary>
+        public abstract partial record CalculusOperator(Entity Expression, Entity Var) : Function
+        {
         }
 
         /// <summary>
@@ -100,14 +115,5 @@ public abstract record TrigonometricFunction : Function
         public Entity Signum() => new Signumf(this);
         /// <summary><see cref="MathS.Abs(Entity)"/></summary>
         public Entity Abs() => new Absf(this);
-
-        /// <summary>
-        /// Describes any node that is a function (e. g. sin, cos, etc.)
-        /// but not an operator or leaf
-        /// </summary>
-        public abstract record Function : ContinuousNode
-        {
-            internal override Priority Priority => Priority.Func;
-        }
     }
 }

Sources/AngouriMath/Core/Entity/Entity.Definition.cs

@@ -47,13 +47,14 @@ internal enum Priority
 
         Sum = 20       | NumericalOperation,
         Minus = 20     | NumericalOperation,
+        /// <summary>For text formats, <see cref="Func"/> is used instead.</summary>
+        LatexCalculusOperation = 30 | NumericalOperation,
         Mul = 40       | NumericalOperation,
         Div = 40       | NumericalOperation,
         Pow = 60       | NumericalOperation,
         Factorial = 70 | NumericalOperation,
         Func = 80      | NumericalOperation,
 
-
         Leaf      = 100 | NumericalOperation,
     }
 #pragma warning restore CA1069 // Enums values should not be duplicated

Sources/AngouriMath/Functions/Output/Latex.Definition.cs

@@ -45,6 +45,11 @@ partial record Entity : ILatexiseable
         /// </code>
         /// </example>
         public abstract string Latexise();
+        /// <summary>
+        /// Calculus operators, unlike other functions, have a <see cref="LatexPriority"/> between addition/subtraction
+        /// and multiplication/division which is different from <see cref="Priority"/>.
+        /// </summary>
+        internal virtual Priority LatexPriority => Priority;
 
         /// <summary>Returns the expression in LaTeX (for example, a / b -> \frac{a}{b})</summary>
         /// <param name="parenthesesRequired">Whether to wrap it with parentheses</param>

Sources/AngouriMath/Functions/Output/Latex/Latex.Arithmetics.Classes.cs

@@ -15,17 +15,17 @@ public partial record Sumf
         {
             /// <inheritdoc/>
             public override string Latexise() =>
-                Augend.Latexise(Augend.Priority < Priority)
-                + (Addend.Latexise(Addend.Priority < Priority) is var addend && addend.StartsWith("-")
+                Augend.Latexise(Augend.LatexPriority < LatexPriority)
+                + (Addend.Latexise(Addend.LatexPriority < LatexPriority) is var addend && addend.StartsWith("-")
                     ? addend : "+" + addend);
         }
 
         public partial record Minusf
         {
             /// <inheritdoc/>
             public override string Latexise() =>
-                Subtrahend.Latexise(Subtrahend.Priority < Priority)
-                + "-" + Minuend.Latexise(Minuend.Priority <= Priority);
+                Subtrahend.Latexise(Subtrahend.LatexPriority < LatexPriority)
+                + "-" + Minuend.Latexise(Minuend.LatexPriority <= LatexPriority);
         }
 
         public partial record Mulf
@@ -43,16 +43,16 @@ public override string Latexise()
                                 return currIn switch
                                 {
                                     // -1, -2, 2i, i, -i, -2i etc. in the front and not (1+i) etc.
-                                    Number { Priority: Priority.Sum } and not Complex { RealPart.IsZero: false, ImaginaryPart.IsZero: false } =>
+                                    Number { LatexPriority: Priority.Sum } and not Complex { RealPart.IsZero: false, ImaginaryPart.IsZero: false } =>
                                         currIn.Latexise(false),
-                                    _ => currIn.Latexise(currIn.Priority < Priority)
+                                    _ => currIn.Latexise(currIn.LatexPriority < LatexPriority)
                                 };
                             case 1:
                                 if (longArray[index - 1] is Integer(-1))
-                                    return $"-{currIn.Latexise(currIn.Priority < Priority)}"; // display "-1 * x * y" as "-x \cdot y", only for the first -1
+                                    return $"-{currIn.Latexise(currIn.LatexPriority < LatexPriority)}"; // display "-1 * x * y" as "-x \cdot y", only for the first -1
                                 break;
                         }
-                        var currOut = currIn.Latexise(currIn.Priority < Priority);
+                        var currOut = currIn.Latexise(currIn.LatexPriority < LatexPriority);
 
                         return (longArray[index - 1], currIn) switch // whether we use juxtaposition and omit \cdot
                         {
@@ -61,20 +61,20 @@ public override string Latexise()
 
                             // Don't juxtapose upright variables with numbers like displaying "var2" for "var*2" since "var2" may be interpreted as one variable.
                             // Also, don't produce upright "ei" (one variable with two chars) for e*i, or "ei^2" for e*i^2.
-                            // but "e (2+i)" and "e (2+i)^2" are fine with the parentheses - so we have the priority check.
+                            // but "e (2+i)" and "e (2+i)^2" are fine with the parentheses - so we have the LatexPriority check.
                             (Variable { IsLatexUprightFormatted: true }
-                                or Complex { ImaginaryPart.IsZero: false, Priority: >= Priority.Mul } /* don't combine upright "i" with an upright variable*/,
-                             Variable { IsLatexUprightFormatted: true } or Number { Priority: >= Priority.Mul }
-                                or Factorialf(Number { Priority: Priority.Leaf } or Variable { IsLatexUprightFormatted: true })
-                                or Powf(Number { Priority: Priority.Leaf } or Variable { IsLatexUprightFormatted: true }
-                                        or Factorialf(Number { Priority: Priority.Leaf } or Variable { IsLatexUprightFormatted: true }), _)) => false,
+                                or Complex { ImaginaryPart.IsZero: false, LatexPriority: >= Priority.Mul } /* don't combine upright "i" with an upright variable*/,
+                             Variable { IsLatexUprightFormatted: true } or Number { LatexPriority: >= Priority.Mul }
+                                or Factorialf(Number { LatexPriority: Priority.Leaf } or Variable { IsLatexUprightFormatted: true })
+                                or Powf(Number { LatexPriority: Priority.Leaf } or Variable { IsLatexUprightFormatted: true }
+                                        or Factorialf(Number { LatexPriority: Priority.Leaf } or Variable { IsLatexUprightFormatted: true }), _)) => false,
                             // 2 * (3/4) instead of 2 (3/4) which is a mixed number (= 2 + 3/4)
-                            (Number { Priority: Priority.Leaf }, { Priority: Priority.Div }) => false,
-                            // 2 * 3 instead of 2 3 (= 23), 2 * 3^4 instead of 2 3^4 (= 23^4), but "(2+i) 2", "2 (2+i)" and "2 (2+i)^2" are fine with the parentheses - so we have the priority check.
-                            (_, Number { Priority: >= Priority.Mul } or Factorialf(Number { Priority: Priority.Leaf })
-                                or Powf(Number { Priority: Priority.Leaf } or Factorialf(Number { Priority: Priority.Leaf }), _)) => false, // Keep the \cdot in "f(x) \cdot -2" "f(x) \cdot 2i" "f(x) \cdot -2i"
-                            (var left, var right) => left.Priority >= right.Priority &&
-                                !(left.Priority == Priority.Div && right.Priority == Priority.Div) // Without \cdot, the fraction lines may appear too closely together.
+                            (Number { LatexPriority: Priority.Leaf }, { LatexPriority: Priority.Div }) => false,
+                            // 2 * 3 instead of 2 3 (= 23), 2 * 3^4 instead of 2 3^4 (= 23^4), but "(2+i) 2", "2 (2+i)" and "2 (2+i)^2" are fine with the parentheses - so we have the LatexPriority check.
+                            (_, Number { LatexPriority: >= Priority.Mul } or Factorialf(Number { LatexPriority: Priority.Leaf })
+                                or Powf(Number { LatexPriority: Priority.Leaf } or Factorialf(Number { LatexPriority: Priority.Leaf }), _)) => false, // Keep the \cdot in "f(x) \cdot -2" "f(x) \cdot 2i" "f(x) \cdot -2i"
+                            (var left, var right) => left.LatexPriority >= right.LatexPriority &&
+                                !(left.LatexPriority == Priority.Div && right.LatexPriority == Priority.Div) // Without \cdot, the fraction lines may appear too closely together.
                         } ? $@"{prevOut} {currOut}" : $@"{prevOut} \cdot {currOut}";
                     });
 
@@ -125,7 +125,7 @@ public override string Latexise()
                 }
                 else
                 {
-                    return "{" + Base.Latexise(Base.Priority <= Priority) + "}^{" + Exponent.Latexise() + "}";
+                    return "{" + Base.Latexise(Base.LatexPriority <= LatexPriority) + "}^{" + Exponent.Latexise() + "}";
                 }
             }
         }
@@ -134,7 +134,7 @@ public partial record Factorialf
         {
             /// <inheritdoc/>
             public override string Latexise() =>
-                Argument.Latexise(Argument.Priority <= Priority) + "!";
+                Argument.Latexise(Argument.LatexPriority <= LatexPriority) + "!";
         }
 
         partial record Signumf

Sources/AngouriMath/Functions/Output/Latex/Latex.Calculus.Classes.cs

@@ -11,16 +11,20 @@ namespace AngouriMath
 {
     partial record Entity
     {
+        partial record CalculusOperator
+        {
+            /// <inheritdoc/>
+            internal override Priority LatexPriority => Priority.LatexCalculusOperation;
+        }
         public partial record Derivativef
         {
             internal static string LatexiseDerivative(Entity expression, Entity var, int iterations)
             {
                 var powerIfNeeded = iterations == 1 ? "" : "^{" + iterations + "}";
-                var varOverDeriv = var is Variable { IsLatexUprightFormatted: false } ? var.Latexise() : @"\left(" + var.Latexise() + @"\right)";
-                string ParenIfNeeded(string paren) => expression.Priority < Priority.Pow ? paren : "";
                 // NOTE: \mathrm{d} is used for upright 'd' following ISO 80000-2 standard.
                 // The differential operator should be upright (roman) to distinguish it from variables, similar to sin, cos, log, etc.
-                return $$"""\frac{\mathrm{d}{{powerIfNeeded}}}{\mathrm{d}{{varOverDeriv}}{{powerIfNeeded}}}{{ParenIfNeeded(@"\left[")}}{{expression.Latexise()}}{{ParenIfNeeded(@"\right]")}}""";
+                return $$"""\frac{\mathrm{d}{{powerIfNeeded}}}{\mathrm{d}{{var.Latexise(var is not Variable { IsLatexUprightFormatted: false })
+                    }}{{powerIfNeeded}}}{{expression.Latexise(expression.LatexPriority < Priority.LatexCalculusOperation)}}""";
             }
             /// <inheritdoc/>
             public override string Latexise() => LatexiseDerivative(Expression, Var, Iterations);
@@ -40,9 +44,7 @@ public override string Latexise()
                 var sb = new StringBuilder();
                 for (int i = 0; i < Iterations; i++)
                     sb.Append(@"\int");
-                sb.Append(@" \left[");
-                sb.Append(Expression.Latexise(false));
-                sb.Append(@"\right]");
+                sb.Append(' ').Append(Expression.Latexise(Expression.LatexPriority < Priority.LatexCalculusOperation));
 
                 // NOTE: \mathrm{d} is used for upright 'd' following ISO 80000-2 standard.
                 // The differential operator should be upright (roman) to distinguish it from variables.
@@ -54,14 +56,7 @@ public override string Latexise()
                 {
                     sb.Append(@"\,");// Leading space before first differential and between differentials
                     sb.Append(@"\mathrm{d}");
-                    if (Var is Variable { IsLatexUprightFormatted: false })
-                        sb.Append(Var.Latexise());
-                    else
-                    {
-                        sb.Append(@"\left(");
-                        sb.Append(Var.Latexise());
-                        sb.Append(@"\right)");
-                    }
+                    sb.Append(Var.Latexise(Var is not Variable { IsLatexUprightFormatted: false }));
                 }
                 return sb.ToString();
             }
@@ -79,23 +74,18 @@ public override string Latexise()
                 switch (ApproachFrom)
                 {
                     case ApproachFrom.Left:
-                        sb.Append(Destination.Latexise(Destination.Priority <= Priority.Pow)).Append("^-");
+                        sb.Append(Destination.Latexise(Destination.LatexPriority <= Priority.Pow)).Append("^-");
                         break;
                     case ApproachFrom.Right:
-                        sb.Append(Destination.Latexise(Destination.Priority <= Priority.Pow)).Append("^+");
+                        sb.Append(Destination.Latexise(Destination.LatexPriority <= Priority.Pow)).Append("^+");
                         break;
                     case ApproachFrom.BothSides:
                         sb.Append(Destination.Latexise());
                         break;
                 }
 
                 sb.Append("} ");
-                if (Expression.Priority < Priority.Pow)
-                    sb.Append(@"\left[");
-                sb.Append(Expression.Latexise());
-                if (Expression.Priority < Priority.Pow)
-                    sb.Append(@"\right]");
-
+                sb.Append(Expression.Latexise(Expression.LatexPriority < Priority.LatexCalculusOperation));
                 return sb.ToString();
             }
         }