Changed creature computations to leverage the MathJS parser (big deal)

app/.meteor/packages

@@ -13,7 +13,6 @@ matb33:collection-hooks
 momentjs:moment
 dburles:mongo-collection-instances
 percolate:migrations
-ecwyne:mathjs
 accounts-google@1.3.2
 splendido:accounts-meld
 email@1.2.3

app/.meteor/versions

@@ -39,7 +39,6 @@ ecmascript@0.12.4
 ecmascript-runtime@0.7.0
 ecmascript-runtime-client@0.8.0
 ecmascript-runtime-server@0.7.1
-ecwyne:mathjs@0.25.0
 ejson@1.1.0
 email@1.2.3
 es5-shim@4.8.0

app/imports/api/creature/creatureComputation.js

@@ -3,7 +3,6 @@
 
 import { ValidatedMethod } from 'meteor/mdg:validated-method';
 import SimpleSchema from 'simpl-schema';
-import schema from '/imports/api/schema.js';
 import { canEditCreature } from '/imports/api/creature/creaturePermission.js';
 import Creatures from "/imports/api/creature/Creatures.js";
 import Attributes from "/imports/api/creature/properties/Attributes.js";
@@ -11,12 +10,13 @@ import Skills from "/imports/api/creature/properties/Skills.js";
 import Effects from "/imports/api/creature/properties/Effects.js";
 import DamageMultipliers from "/imports/api/creature/properties/DamageMultipliers.js";
 import Classes from "/imports/api/creature/properties/Classes.js";
+import * as math from 'mathjs';
 
 export const recomputeCreature = new ValidatedMethod({
 
   name: "Creatures.methods.recomputeCreature",
 
-  validate: schema({
+  validate: new SimpleSchema({
     charId: { type: String }
   }).validator(),
 
@@ -99,37 +99,9 @@ function writeCreature(char) {
 
 function writeCreatureDoc(char) {
   // Store all the variables, using the same priority as computation evaluation
-  // Attributes
   let variables = {};
-  for (let key in char.atts){
+  for (let key in char.variables){
-    variables[key] = char.atts[key].result;
+    variables[key] = char.variables[key].result;
-    if (
-      char.atts[key].attributeType === 'ability' &&
-      !variables.hasOwnProperty(key + 'Mod')
-    ){
-      variables[key + 'Mod'] = char.atts[key].mod;
-    }
-  }
-  for (let key in char.skills){
-    if (!variables.hasOwnProperty(key)){
-      variables[key] = char.skills[key].result;
-    }
-  }
-  // Damage Multipliers
-  for (let key in char.dms){
-    if (!variables.hasOwnProperty(key)){
-      variables[key] = char.dms[key].result;
-    }
-  }
-  // Class levels
-  for (let key in char.classes){
-    if (!variables.hasOwnProperty(key + 'Level')){
-      variables[key + 'Level'] = char.classes[key].level;
-    }
-  }
-  // Creature level
-  if (!variables.hasOwnProperty('level')){
-    variables['level'] = char.level;
   }
 
   // Write the creature
@@ -139,13 +111,6 @@ function writeCreatureDoc(char) {
 /*
  * Write all the attributes from the in-memory char object to the Attirbute docs
  */
-
-/**
- * writeAttributes - description
- *
- * @param  {type} char description
- * @returns {type}      description
- */
 function writeAttributes(char) {
   let bulkWriteOps =  _.map(char.atts, (att, variableName) => {
     let op = {
@@ -261,7 +226,7 @@ function writeDamageMultipliers(char) {
 
  /**
   * Get the creature's data from the database and build an in-memory model that
-  * can be computed. Hits 6 database collections with indexed queries.
+  * can be computed. Hits 7 database collections with indexed queries.
   *
   * @param  {type} charId description
   * @returns {type}        description
@@ -273,14 +238,16 @@ function buildCreature(charId){
     skills: {},
     dms: {},
     classes: {},
+    variables: {},
     otherEffects: [],
     computedEffects: [],
     level: 0,
   };
   // Fetch the attributes of the creature and add them to an object for quick lookup
   Attributes.find({charId}).forEach(attribute => {
-    if (!char.atts[attribute.variableName]){
+    const key = attribute.variableName;
-      char.atts[attribute.variableName] = {
+    if (!char.atts[key]){
+      char.atts[key] = {
         computed: false,
         busyComputing: false,
         type: "attribute",
@@ -295,13 +262,27 @@ function buildCreature(charId){
         max: Number.POSITIVE_INFINITY,
         effects: [],
       };
+      char.variables[key] = char.atts[key];
+      if (attribute.type === 'ability' && !char.variables[key + "Mod"]){
+        char.variables[key + "Mod"] = {
+          type: "abilityMod",
+          ability: char.atts[key],
+          get result(){
+            return this.ability.mod;
+          },
+          get computed(){
+            return this.ability.computed;
+          },
+        }
+      }
     }
   });
 
   // Fetch the skills of the creature and store them
   Skills.find({charId}).forEach(skill => {
-    if (!char.skills[skill.variableName]){
+    const key = skill.variableName;
-      char.skills[skill.variableName] = {
+    if (!char.skills[key]){
+      char.skills[key] = {
         computed: false,
         busyComputing: false,
         type: "skill",
@@ -321,13 +302,17 @@ function buildCreature(charId){
         effects: [],
         proficiencies: [],
       };
+      if (!char.variables[key]){
+        char.variables[key] = char.skills[key];
+      }
     }
   });
 
   // Fetch the damage multipliers of the creature and store them
   DamageMultipliers.find({charId}).forEach(damageMultiplier =>{
-    if (!char.dms[damageMultiplier.variableName]){
+    const key = damageMultiplier.variableName
-      char.dms[damageMultiplier.variableName] = {
+    if (!char.dms[key]){
+      char.dms[key] = {
         computed: false,
         busyComputing: false,
         type: "damageMultiplier",
@@ -337,19 +322,53 @@ function buildCreature(charId){
         vulnerabilityCount: 0,
         effects: [],
       };
+      if (!char.variables[key]){
+        char.variables[key] = char.dms[key];
+      }
     }
   });
 
   // Fetch the class levels and store them
   // don't use the word "class" it's reserved
+  const levelOverwritten = !!char.variables['level']
+  if (!levelOverwritten){
+    char.variables['level'] = {
+      result: 0,
+      type: 'characterLevel',
+      computed: true,
+    };
+  }
   Classes.find({charId}).forEach(cls => {
     const strippedCls = cls.name.replace(/\s+/g, '');
     if (!char.classes[strippedCls]){
       char.classes[strippedCls] = {level: cls.level};
       char.level += cls.level;
+      if (!char.variables[strippedCls]){
+        char.variables[strippedCls + "Level"] = {
+          result: cls.level,
+          type: 'classLevel',
+          computed: true,
+        };
+      }
+      if (!levelOverwritten){
+        char.variables['level'].result = char.level;
+      }
     }
   });
 
+  // Add direct properties from creature to variable list
+  const fields = { xp: 1, weightCarried: 1};
+  const creature = Creatures.findOne(charId, {fields});
+  for (let key in fields){
+    if (!char.variables[key]){
+      char.variables[key] = {
+        result: creature[key] || 0,
+        type: 'creatureProperty',
+        computed: true,
+      };
+    }
+  }
+
   // Fetch the effects which apply to each stat and store them under the attribute
   Effects.find({
     charId: charId,
@@ -386,7 +405,6 @@ function buildCreature(charId){
   return char;
 };
 
-
 /**
  *  Compute the creature's stats in-place, returns the same char object
  * @param  {type} char description
@@ -422,6 +440,11 @@ export function computeCreature(char){
  * @returns {type}      description
  */
 function computeStat(stat, char){
+  // Ability mods aren't stats, use the stat they are based off of
+  if (stat.type === 'abilityMod'){
+    stat = stat.ability;
+  }
+
   // If the stat is already computed, skip it
   if (stat.computed) return;
 
@@ -435,6 +458,7 @@ function computeStat(stat, char){
     return;
   }
 
+
   // Iterate over each effect which applies to the stat
   for (i in stat.effects){
     computeEffect(stat.effects[i], char);
@@ -451,11 +475,7 @@ function computeStat(stat, char){
 }
 
  /**
-  * const computeEffect - Compute a single effect on a creature
+  * Compute a the result of a single effect
-  *
-  * @param  {Object} effect The effect to compute
-  * @param  {Object} char   The char document to compute with
-  * @returns {undefined}        description
   */
 function computeEffect(effect, char){
   if (effect.computed) return;
@@ -465,80 +485,67 @@ function computeEffect(effect, char){
     effect.result = effect.calculation;
   } else if(_.contains(["advantage", "disadvantage", "fail"], effect.operation)){
     effect.result = 1;
-  } else if (_.isString(effect.calculation)){
+  } else {
 		effect.result = evaluateCalculation(effect.calculation, char);
 	}
   effect.computed = true;
   char.computedEffects.push(effect);
 };
 
-
 /**
  * Apply a computed effect to its stat
- *
- * @param  {type} effect description
- * @param  {type} stat   description
- * @returns {type}        description
  */
 function applyEffect(effect, stat){
-  // Take the largest base value
+  if (!_.has(stat, effect.operation)){
-  if (effect.operation === "base"){
+    return;
-    if (!_.has(stat, "base")) return;
-    stat.base = effect.result > stat.base ? effect.result : stat.base;
   }
-  // Add all adds together
+  switch(effect.operation){
-  else if (effect.operation === "add"){
+    case "base":
-    if (!_.has(stat, "add")) return;
+      // Take the largest base value
-    stat.add += effect.result;
+      stat.base = effect.result > stat.base ? effect.result : stat.base;
-  }
+      break;
-  else if (effect.operation === "mul"){
+    case "add":
-    if (!_.has(stat, "mul")) return;
+      // Add all adds together
-    stat.mul *= effect.result;
+      stat.add += effect.result;
-  }
+      break;
-  // Take the largest min value
+    case "mul":
-  if (effect.operation === "min"){
+      // Multiply the muls together
-    if (!_.has(stat, "min")) return;
+      stat.mul *= effect.result;
-    stat.min = effect.result > stat.min ? effect.result : stat.min;
+      break;
-  }
+    case "min":
-  // Take the smallest max value
+      // Take the largest min value
-  if (effect.operation === "max"){
+      stat.min = effect.result > stat.min ? effect.result : stat.min;
-    if (!_.has(stat, "max")) return;
+      break;
-    stat.max = effect.result < stat.max ? effect.result : stat.max;
+    case "max":
-  }
+      // Take the smallest max value
-  // Sum number of advantages
+      stat.max = effect.result < stat.max ? effect.result : stat.max;
-  else if (effect.operation === "advantage"){
+      break;
-    if (!_.has(stat, "advantage")) return;
+    case "advantage":
-    stat.advantage++;
+      // Sum number of advantages
-  }
+      stat.advantage++;
-  // Sum number of disadvantages
+      break;
-  else if (effect.operation === "disadvantage"){
+    case "disadvantage":
-    if (!_.has(stat, "disadvantage")) return;
+      // Sum number of disadvantages
-    stat.disadvantage++;
+      stat.disadvantage++;
-  }
+      break;
-  // Add all passive adds together
+    case "passiveAdd":
-  else if (effect.operation === "passiveAdd"){
+      // Add all passive adds together
-    if (!_.has(stat, "passiveAdd")) return;
+      stat.passiveAdd += effect.result;
-    stat.passiveAdd += effect.result;
+      break;
-  }
+    case "fail":
-  // Sum number of fails
+      // Sum number of fails
-  else if (effect.operation === "fail"){
+      stat.fail++;
-    if (!_.has(stat, "fail")) return;
+      break;
-    stat.fail++;
+    case "conditional":
-  }
+      // Sum number of conditionals
-  // Sum number of conditionals
+      stat.conditional++;
-  else if (effect.operation === "conditional"){
+      break;
-    if (!_.has(stat, "conditional")) return;
-    stat.conditional++;
   }
 };
 
 
 /**
  * Combine the results of multiple effects to get the result of the stat
- *
- * @param  {type} stat description
- * @param  {type} char description
- * @returns {type}      description
  */
 function combineStat(stat, char){
   if (stat.type === "attribute"){
@@ -553,16 +560,11 @@ function combineStat(stat, char){
 
 /**
  * combineAttribute - Combine attributes's results into final values
- *
- * @param  {type} stat description
- * @param  {type} char description
- * @returns {type}      description
  */
 function combineAttribute(stat, char){
   stat.result = (stat.base + stat.add) * stat.mul;
   if (stat.result < stat.min) stat.result = stat.min;
   if (stat.result > stat.max) stat.result = stat.max;
-  // Round everything that isn't the carry multiplier
   if (!stat.decimal) stat.result = Math.floor(stat.result);
   if (stat.attributeType === "ability") {
     stat.mod = Math.floor((stat.result - 10) / 2);
@@ -571,11 +573,7 @@ function combineAttribute(stat, char){
 
 
 /**
- * combineSkill - Combine skills results into final values
+ * Combine skills results into final values
- *
- * @param  {type} stat description
- * @param  {type} char description
- * @returns {type}      description
  */
 function combineSkill(stat, char){
   for (i in stat.proficiencies){
@@ -608,11 +606,7 @@ function combineSkill(stat, char){
 }
 
 /**
- * combineDamageMultiplier - Combine damageMultiplier's results into final values
+ * Combine damageMultiplier's results into final values
- *
- * @param  {type} stat description
- * @param  {type} char description
- * @returns {type}      description
  */
 function combineDamageMultiplier(stat, char){
   if (stat.immunityCount) return 0;
@@ -625,69 +619,47 @@ function combineDamageMultiplier(stat, char){
   }
 }
 
+/**
+ * Get the value of a key, compute it if necessary
+ */
+function getComputedValueOfKey(sub, char){
+  const stat = char.variables[sub];
+  if (!stat) return null;
+  if (!stat.computed){
+    computeStat(stat, char);
+  }
+  return stat.result;
+};
 
 /**
- * evaluateCalculation - Evaluate a string computation in the context of  a char
+ * Evaluate a string computation in the context of a char
- *
- * @param  {type} string description
- * @param  {type} char   description
- * @returns {type}        description
  */
 function evaluateCalculation(string, char){
   if (!string) return string;
-  // Replace all the string variables with numbers if possible
+  // Parse the string using mathjs
-  string = string.replace(/\w*[a-z]\w*/gi, function(sub){
+  let calc;
-    // Attributes
+  try {
-    if (char.atts[sub]){
+    calc = math.parse(string);
-      if (!char.atts[sub].computed){
+  } catch (e) {
-        computeStat(char.atts[sub], char);
+    return string;
-      }
+  }
-      return char.atts[sub].result;
+  // Replace all symbols with known values
+  let substitutedCalc = calc.transform(node => {
+    if (node.isSymbolNode) {
+      let val = getComputedValueOfKey(node.name, char);
+      if (val === null) return node;
+      return new math.expression.node.ConstantNode(val);
     }
-    // Modifiers
+    else {
-    if (/^\w+mod$/i.test(sub)){
+      return node;
-      var slice = sub.slice(0, -3);
-      if (char.atts[slice]){
-        if (!char.atts[slice].computed){
-          computeStat(char.atts[sub], char);
-        }
-        return char.atts[slice].mod;
-      }
     }
-    // Skills
-    if (char.skills[sub]){
-      if (!char.skills[sub].computed){
-        computeStat(char.skills[sub], char);
-      }
-      return char.skills[sub].result;
-    }
-    // Damage Multipliers
-    if (char.dms[sub]){
-      if (!char.dms[sub].computed){
-        computeStat(char.dms[sub], char);
-      }
-      return char.dms[sub].result;
-    }
-    // Class levels
-    if (/^\w+levels?$/i.test(sub)){
-      //strip out "level(s)"
-      var className = sub.replace(/levels?$/i, "");
-      return char.classes[className] && char.classes[className].level;
-    }
-    // Creature level
-    if (sub  === "level"){
-      return char.level;
-    }
-    // Give up
-    return sub;
   });
 
-  // Evaluate the expression to a number or return it as is.
+  // Evaluate the expression to a number or return with substitutions
   try {
-    var result = math.eval(string); // math.eval is safe
+    return substitutedCalc.eval();
-    return result;
   } catch (e){
-    return string;
+    return substitutedCalc.toString();
   }
 };
 
@@ -699,7 +671,7 @@ function evaluateCalculation(string, char){
 export const recomputeCreatureXP = new ValidatedMethod({
   name: "Creatures.methods.recomputeCreatureXP",
 
-  validate: schema({
+  validate: new SimpleSchema({
     charId: { type: String }
   }).validator(),
 
@@ -729,7 +701,7 @@ export const recomputeCreatureXP = new ValidatedMethod({
 export const recomputeCreatureWeightCarried = new ValidatedMethod({
   name: "Creature.methods.recomputeCreatureWeightCarried",
 
-  validate: schema({
+  validate: new SimpleSchema({
     charId: { type: String }
   }).validator(),
 

app/lib/functions/evaluate.js

@@ -1,104 +0,0 @@
-// if we want to add more functions, consider pulling out into its own file
-(function() {
-    math.import({
-        "if": function(pred, a, b) {
-            return (!!(pred)) ? a : b;
-        }
-    });
-})();
-
-//evaluates a calculation string
-evaluate = function(charId, string, opts){
-    var spellListId = opts && opts.spellListId;
-	if (!string) return string;
-	string = string.replace(/\b[a-z,1-9]+\b/gi, function(sub){
-		//fields
-		if (Schemas.Character.schema(sub)){
-			return Characters.calculate.fieldValue(charId, sub);
-		}
-		//ability modifiers
-		var abilityMods = [
-			"strengthMod",
-			"dexterityMod",
-			"constitutionMod",
-			"intelligenceMod",
-			"wisdomMod",
-			"charismaMod",
-		];
-		if (_.contains(abilityMods, sub)){
-			var slice = sub.slice(0, -3);
-			try {
-				return Characters.calculate.abilityMod(charId, slice);
-			} catch (e){
-				return sub;
-			}
-		}
-		//class levels
-		if (/\w+levels?\b/gi.test(sub)){
-			//strip out "level"
-			var className = sub.replace(/levels?\b/gi, "");
-			var cls = Classes.findOne({charId: charId, name: className});
-			return cls && cls.level || sub;
-		}
-		//character level
-		if (sub.toUpperCase()  === "LEVEL"){
-			return Characters.calculate.level(charId);
-		}
-        if (spellListId && sub.toUpperCase() === "DC") {
-            var list = SpellLists.findOne(spellListId);
-            if (list && list.saveDC){
-                return evaluate(charId, list.saveDC);
-            }
-        }
-        if (spellListId && sub.toUpperCase() === "ATTACKBONUS") {
-            var list = SpellLists.findOne(spellListId);
-            if (list && list.attackBonus){
-                return evaluate(charId, list.attackBonus);
-            }
-        }
-		return sub;
-	});
-	try {
-		var result = math.eval(string);
-		return result;
-	} catch (e){
-		return string;
-	}
-};
-
-//takes a string with {calculations} and returns it with the results
-//of the calculations returned in place
-evaluateString = function(charId, string){
-	//define brackets as curly brackets around anything that isn't a curly bracket
-	if (!string) return string;
-	var brackets = /\{[^\{\}]*\}/g;
-	var result = string.replace(brackets, function(exp){
-		exp = exp.replace(/(\{|\})/g, ""); //remove curly brackets
-		return evaluate(charId, exp);
-	});
-	return result;
-};
-
-evaluateSpellString = function (charId, spellListId, string) {
-    //define brackets as curly brackets around anything that isn't a curly bracket
-	if (!string) return string;
-	var brackets = /\{[^\{\}]*\}/g;
-	var result = string.replace(brackets, function(exp){
-		exp = exp.replace(/(\{|\})/g, ""); //remove curly brackets
-		return evaluate(charId, exp, {spellListId});
-	});
-	return result;
-}
-
-//returns the value of the effect if it exists,
-//otherwise returns the result of the calculation if it exists,
-//otherwise returns 0
-evaluateEffect = function(charId, effect){
-	if (_.isFinite(effect.value)){
-		return effect.value;
-	} else if (_.isString(effect.calculation)){
-		return +evaluate(charId, effect.calculation);
-	} else {
-		return 0;
-	}
-};

app/package-lock.json

@@ -199,6 +199,11 @@
         "delayed-stream": "~1.0.0"
       }
     },
+    "complex.js": {
+      "version": "2.0.11",
+      "resolved": "https://registry.npmjs.org/complex.js/-/complex.js-2.0.11.tgz",
+      "integrity": "sha512-6IArJLApNtdg1P1dFtn3dnyzoZBEF0MwMnrfF1exSBRpZYoy4yieMkpZhQDC0uwctw48vii0CFVyHfpgZ/DfGw=="
+    },
     "concat-map": {
       "version": "0.0.1",
       "resolved": "https://registry.npmjs.org/concat-map/-/concat-map-0.0.1.tgz",
@@ -264,6 +269,11 @@
       "resolved": "https://registry.npmjs.org/decamelize/-/decamelize-1.2.0.tgz",
       "integrity": "sha1-9lNNFRSCabIDUue+4m9QH5oZEpA="
     },
+    "decimal.js": {
+      "version": "10.0.2",
+      "resolved": "https://registry.npmjs.org/decimal.js/-/decimal.js-10.0.2.tgz",
+      "integrity": "sha512-qL5tUTXAWjB5cSBfm0V2a4jO5FaDLumCfwc/0f7WaTOT3WU8pIeq2HHrd98eXHtbey4qFWlaPzfml1JWIoO9TQ=="
+    },
     "deep-extend": {
       "version": "0.6.0",
       "resolved": "https://registry.npmjs.org/deep-extend/-/deep-extend-0.6.0.tgz",
@@ -301,6 +311,11 @@
         "once": "^1.4.0"
       }
     },
+    "escape-latex": {
+      "version": "1.2.0",
+      "resolved": "https://registry.npmjs.org/escape-latex/-/escape-latex-1.2.0.tgz",
+      "integrity": "sha512-nV5aVWW1K0wEiUIEdZ4erkGGH8mDxGyxSeqPzRNtWP7ataw+/olFObw7hujFWlVjNsaDFw5VZ5NzVSIqRgfTiw=="
+    },
     "execa": {
       "version": "1.0.0",
       "resolved": "https://registry.npmjs.org/execa/-/execa-1.0.0.tgz",
@@ -363,6 +378,11 @@
         "mime-types": "^2.1.12"
       }
     },
+    "fraction.js": {
+      "version": "4.0.12",
+      "resolved": "https://registry.npmjs.org/fraction.js/-/fraction.js-4.0.12.tgz",
+      "integrity": "sha512-8Z1K0VTG4hzYY7kA/1sj4/r1/RWLBD3xwReT/RCrUCbzPszjNQCCsy3ktkU/eaEqX3MYa4pY37a52eiBlPMlhA=="
+    },
     "fs.realpath": {
       "version": "1.0.0",
       "resolved": "https://registry.npmjs.org/fs.realpath/-/fs.realpath-1.0.0.tgz",
@@ -529,6 +549,11 @@
       "resolved": "https://registry.npmjs.org/isstream/-/isstream-0.1.2.tgz",
       "integrity": "sha1-R+Y/evVa+m+S4VAOaQ64uFKcCZo="
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+    "javascript-natural-sort": {
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+      "resolved": "https://registry.npmjs.org/javascript-natural-sort/-/javascript-natural-sort-0.7.1.tgz",
+      "integrity": "sha1-+eIwPUUH9tdDVac2ZNFED7Wg71k="
+    },
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       "resolved": "https://registry.npmjs.org/jsbn/-/jsbn-0.1.1.tgz",
@@ -795,6 +820,21 @@
         "p-defer": "^1.0.0"
       }
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+    "mathjs": {
+      "version": "5.5.0",
+      "resolved": "https://registry.npmjs.org/mathjs/-/mathjs-5.5.0.tgz",
+      "integrity": "sha512-qvCNNcpPFpk85EYFiY9+jyWClFHBNqQlUQ3zKGy/EuLSicuJCmxEtHEQxThL0macmbgl1dzmenrgDbRpGE3QRg==",
+      "requires": {
+        "complex.js": "2.0.11",
+        "decimal.js": "10.0.2",
+        "escape-latex": "1.2.0",
+        "fraction.js": "4.0.12",
+        "javascript-natural-sort": "0.7.1",
+        "seed-random": "2.2.0",
+        "tiny-emitter": "2.1.0",
+        "typed-function": "1.1.0"
+      }
+    },
     "mem": {
       "version": "4.0.0",
       "resolved": "https://registry.npmjs.org/mem/-/mem-4.0.0.tgz",
@@ -1406,6 +1446,37 @@
           "requires": {
             "inherits": "~2.0.1",
             "readable-stream": "^2.0.2"
+          },
+          "dependencies": {
+            "readable-stream": {
+              "version": "2.3.6",
+              "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
+              "integrity": "sha512-tQtKA9WIAhBF3+VLAseyMqZeBjW0AHJoxOtYqSUZNJxauErmLbVm2FW1y+J/YA9dUrAC39ITejlZWhVIwawkKw==",
+              "requires": {
+                "core-util-is": "~1.0.0",
+                "inherits": "~2.0.3",
+                "isarray": "~1.0.0",
+                "process-nextick-args": "~2.0.0",
+                "safe-buffer": "~5.1.1",
+                "string_decoder": "~1.1.1",
+                "util-deprecate": "~1.0.1"
+              },
+              "dependencies": {
+                "inherits": {
+                  "version": "2.0.3",
+                  "resolved": "https://registry.npmjs.org/inherits/-/inherits-2.0.3.tgz",
+                  "integrity": "sha1-Yzwsg+PaQqUC9SRmAiSA9CCCYd4="
+                }
+              }
+            },
+            "string_decoder": {
+              "version": "1.1.1",
+              "resolved": "https://registry.npmjs.org/string_decoder/-/string_decoder-1.1.1.tgz",
+              "integrity": "sha512-n/ShnvDi6FHbbVfviro+WojiFzv+s8MPMHBczVePfUpDJLwoLT0ht1l4YwBCbi8pJAveEEdnkHyPyTP/mzRfwg==",
+              "requires": {
+                "safe-buffer": "~5.1.0"
+              }
+            }
           }
         },
         "stream-http": {
@@ -1418,6 +1489,37 @@
             "readable-stream": "^2.3.3",
             "to-arraybuffer": "^1.0.0",
             "xtend": "^4.0.0"
+          },
+          "dependencies": {
+            "readable-stream": {
+              "version": "2.3.6",
+              "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
+              "integrity": "sha512-tQtKA9WIAhBF3+VLAseyMqZeBjW0AHJoxOtYqSUZNJxauErmLbVm2FW1y+J/YA9dUrAC39ITejlZWhVIwawkKw==",
+              "requires": {
+                "core-util-is": "~1.0.0",
+                "inherits": "~2.0.3",
+                "isarray": "~1.0.0",
+                "process-nextick-args": "~2.0.0",
+                "safe-buffer": "~5.1.1",
+                "string_decoder": "~1.1.1",
+                "util-deprecate": "~1.0.1"
+              },
+              "dependencies": {
+                "inherits": {
+                  "version": "2.0.3",
+                  "resolved": "https://registry.npmjs.org/inherits/-/inherits-2.0.3.tgz",
+                  "integrity": "sha1-Yzwsg+PaQqUC9SRmAiSA9CCCYd4="
+                }
+              }
+            },
+            "string_decoder": {
+              "version": "1.1.1",
+              "resolved": "https://registry.npmjs.org/string_decoder/-/string_decoder-1.1.1.tgz",
+              "integrity": "sha512-n/ShnvDi6FHbbVfviro+WojiFzv+s8MPMHBczVePfUpDJLwoLT0ht1l4YwBCbi8pJAveEEdnkHyPyTP/mzRfwg==",
+              "requires": {
+                "safe-buffer": "~5.1.0"
+              }
+            }
           }
         },
         "string_decoder": {
@@ -1857,6 +1959,11 @@
       "resolved": "https://registry.npmjs.org/safer-buffer/-/safer-buffer-2.1.2.tgz",
       "integrity": "sha512-YZo3K82SD7Riyi0E1EQPojLz7kpepnSQI9IyPbHHg1XXXevb5dJI7tpyN2ADxGcQbHG7vcyRHk0cbwqcQriUtg=="
     },
+    "seed-random": {
+      "version": "2.2.0",
+      "resolved": "https://registry.npmjs.org/seed-random/-/seed-random-2.2.0.tgz",
+      "integrity": "sha1-KpsZ4lCoFwmSMaW5mk2vgLf77VQ="
+    },
     "semver": {
       "version": "5.4.1",
       "resolved": "https://registry.npmjs.org/semver/-/semver-5.4.1.tgz",
@@ -1997,6 +2104,11 @@
         "uid-number": "^0.0.6"
       }
     },
+    "tiny-emitter": {
+      "version": "2.1.0",
+      "resolved": "https://registry.npmjs.org/tiny-emitter/-/tiny-emitter-2.1.0.tgz",
+      "integrity": "sha512-NB6Dk1A9xgQPMoGqC5CVXn123gWyte215ONT5Pp5a0yt4nlEoO1ZWeCwpncaekPHXO60i47ihFnZPiRPjRMq4Q=="
+    },
     "tough-cookie": {
       "version": "2.4.3",
       "resolved": "https://registry.npmjs.org/tough-cookie/-/tough-cookie-2.4.3.tgz",
@@ -2026,6 +2138,11 @@
       "resolved": "https://registry.npmjs.org/tweetnacl/-/tweetnacl-0.14.5.tgz",
       "integrity": "sha1-WuaBd/GS1EViadEIr6k/+HQ/T2Q="
     },
+    "typed-function": {
+      "version": "1.1.0",
+      "resolved": "https://registry.npmjs.org/typed-function/-/typed-function-1.1.0.tgz",
+      "integrity": "sha512-TuQzwiT4DDg19beHam3E66oRXhyqlyfgjHB/5fcvsRXbfmWPJfto9B4a0TBdTrQAPGlGmXh/k7iUI+WsObgORA=="
+    },
     "uid-number": {
       "version": "0.0.6",
       "resolved": "https://registry.npmjs.org/uid-number/-/uid-number-0.0.6.tgz",

app/package.json

@@ -20,6 +20,7 @@
     "css-box-shadow": "^1.0.0-3",
     "fibers": "^2.0.2",
     "lodash": "^4.17.11",
+    "mathjs": "^5.5.0",
     "meteor-node-stubs": "^0.3.3",
     "qrcode": "^1.3.3",
     "simpl-schema": "^1.5.5",