line segments

Author: dqnykamp

lib/converters/ast-to-latex.js

@@ -167,6 +167,9 @@ const operators = {
   "vec": function (operands) {
     return "\\vec{" + operands[0] + "}";
   },
+  "linesegment": function (operands) {
+    return "\\overline{" + operands.join(" ") + "}";
+  },
   "angle": function (operands, use_shorthand) {
     if (use_shorthand) {
       return "\\angle " + operands.join("");
@@ -565,7 +568,7 @@ class astToLatex {
       operator === 'list' ||
       operator === 'set' || operator === 'vector' || operator === 'altvector' ||
       operator === '|' || operator === ':' ||
-      operator === 'binom' || operator === 'vec') {
+      operator === 'binom' || operator === 'vec' || operator === 'linesegment') {
       return operators[operator](operands.map(function (v, i) {
         return this.statement(v);
       }.bind(this)));

lib/converters/ast-to-text.js

@@ -72,6 +72,7 @@ const unicode_operators = {
   ":": function (operands) { return operands[0] + " : " + operands[1]; },
   "binom": function (operands) { return "binom( " + operands[0] + ", " + operands[1] + " )"; },
   "vec": function (operands) { return "vec(" + operands[0] + ")"; },
+  "linesegment": function (operands) { return "linesegment( " + operands.join(", ") + " )"; },
   "angle": function (operands, use_shorthand) {
     if (use_shorthand) {
       return "∠" + operands.join("");
@@ -132,6 +133,7 @@ const nonunicode_operators = {
   ":": function (operands) { return operands[0] + " : " + operands[1]; },
   "binom": function (operands) { return "binom( " + operands[0] + ", " + operands[1] + " )"; },
   "vec": function (operands) { return "vec(" + operands[0] + ")"; },
+  "linesegment": function (operands) { return "linesegment( " + operands.join(", ") + " )"; },
   "angle": function (operands, use_shorthand) {
     if (use_shorthand) {
       return "angle " + operands.join("");
@@ -571,7 +573,7 @@ class astToText {
       || operator === 'list'
       || operator === 'set' || operator === 'vector' || operator === 'altvector'
       || operator === '|' || operator === ':'
-      || operator === 'binom' || operator === 'vec') {
+      || operator === 'binom' || operator === 'vec' || operator === 'linesegment') {
       return this.operators[operator](operands.map(function (v, i) {
         return this.statement(v);
       }.bind(this)));

lib/converters/latex-to-ast.js

@@ -386,6 +386,7 @@ const operatorSymbolsDefault = {
   'frac': { nargs: 2, substitute: "/" },
   'binom': { nargs: 2 },
   'vec': { nargs: 1 },
+  'overline': { nargs: 1, substitute: "linesegment", remove_products: true },
 };
 
 const unitsDefault = get_all_units();
@@ -1299,14 +1300,23 @@ class latexToAst {
 
         let nargs = this.operatorSymbols[result].nargs;
 
+        let remove_products = this.operatorSymbols[result].remove_products;
+
         let args = [];
 
         for (let i = 0; i < nargs; i++) {
 
           if (this.token.token_type === '{') {
             this.advance();
 
-            args.push(this.statement({ parse_absolute_value: parse_absolute_value }));
+            let new_arg = this.statement({ parse_absolute_value: parse_absolute_value });
+
+            if (remove_products && Array.isArray(new_arg) && new_arg[0] === "*") {
+              args.push(...new_arg.slice(1))
+            } else {
+              args.push(new_arg);
+            }
+
             if (this.token.token_type !== '}') {
               throw new ParseError("Expecting }", this.lexer.location);
             }

lib/converters/text-to-ast.js

@@ -390,7 +390,7 @@ const appliedFunctionSymbolsDefault = [
 const functionSymbolsDefault = ['f', 'g'];
 
 // operators must be given an argument
-const operatorSymbolsDefault = ['binom', 'vec'];
+const operatorSymbolsDefault = ['binom', 'vec', 'linesegment'];
 
 const unitsDefault = get_all_units();
 

spec/quick_ast-to-latex.spec.js

@@ -846,6 +846,14 @@ const objectsToTest = [
     'ast': ['vec', 'a'],
     'latex': '\\vec{a}',
   },
+  {
+    'ast': ['linesegment', 'A', 'B'],
+    'latex': '\\overline{A B}',
+  },
+  {
+    'ast': ['linesegment', ['prime', 'A'], ['prime', 'B']],
+    'latex': '\\overline{A\' B\'}',
+  },
   {
     'ast': ['apply', 'floor', 'a'],
     'latex': '\\left\\lfloor a \\right\\rfloor',

spec/quick_ast-to-text.spec.js

@@ -795,6 +795,14 @@ const objectsToTest = [
     'ast': ['vec', 'a'],
     'text': 'vec(a)',
   },
+  {
+    'ast': ['linesegment', 'A', 'B'],
+    'text': 'linesegment( A, B )',
+  },
+  {
+    'ast': ['linesegment', ['prime', 'A'], ['prime', 'B']],
+    'text': 'linesegment( A\', B\' )',
+  },
   {
     'ast': ['apply', 'floor', 'a'],
     'text': 'floor(a)',

spec/quick_latex-to-ast.spec.js

@@ -489,6 +489,8 @@ var trees = {
   '\\vec ab': ["*", ["vec", "a"], "b"],
   '\\vec2': ["vec", 2],
   '\\vec2a': ["*", ["vec", 2], "a"],
+  '\\overline{AB}': ["linesegment", "A", "B"],
+  '\\overline{A\'B\'}': ["linesegment", ["prime", "A"], ["prime", "B"]],
   '\\lfloor a \\rfloor': ["apply", "floor", "a"],
   '\\lfloor1.5\\rfloor2': ["*", ["apply", "floor", 1.5], 2],
   '\\lceil a \\rceil': ["apply", "ceil", "a"],

spec/quick_text-to-ast-to-text.spec.js

@@ -304,6 +304,7 @@ var inputs = [
   'nPr(x,y)',
   'binom(x,y)',
   'vec(a)',
+  'linesegment(A,B)',
   'floor(a)',
   'ceil(a)',
   'round(a)',

spec/quick_text-to-ast.spec.js

@@ -445,6 +445,8 @@ var trees = {
   'nCr(x,y)': ["apply", "nCr", ["tuple", "x", "y"]],
   'binom(x,y)': ["binom", "x", "y"],
   'vec(a)': ["vec", "a"],
+  'linesegment(A,B)': ["linesegment", "A", "B"],
+  'linesegment(A\',B\')': ["linesegment", ["prime", "A"], ["prime", "B"]],
   'floor(a)': ["apply", "floor", "a"],
   'ceil(a)': ["apply", "ceil", "a"],
   'round(a)': ["apply", "round", "a"],