web: Update nullable number handling

web/src/components/CaseBuilder/CaseBuilder.tsx

@@ -13,7 +13,6 @@ import "tabulator-tables/dist/css/tabulator.min.css";
 import "../Common/Forms/Tables.css";
 import { useState } from "react";
 import Footer from "./Footer";
-import { validate } from "../../core/Data/validate";
 import { offerDownload } from "../Common/io";
 import { preprocess } from "../../core/Operations/preprocessing";
 import Toast from "../Common/Forms/Toast";
@@ -68,19 +67,14 @@ const CaseBuilder = () => {
     setAndSaveScenario(newScenario);
   };
 
-  const onLoad = (scenario: UnitCommitmentScenario) => {
-    const preprocessed = preprocess(
-      scenario,
-    ) as unknown as UnitCommitmentScenario;
-
-    // Validate and assign default values
-    if (!validate(preprocessed)) {
-      setToastMessage("Error loading JSON file");
-      console.error(validate.errors);
+  const onLoad = (data: any) => {
+    const json = JSON.parse(data);
+    const [scenario, err] = preprocess(json);
+    if (err) {
+      setToastMessage(err.message);
       return;
     }
-
-    setAndSaveScenario(preprocessed);
+    setAndSaveScenario(scenario!);
     setToastMessage("Data loaded successfully");
   };
 

web/src/components/CaseBuilder/Header.tsx

@@ -22,8 +22,7 @@ function Header(props: HeaderProps) {
 
   function onLoad() {
     fileElem.current!.showFilePicker((data: any) => {
-      const scenario = JSON.parse(data) as UnitCommitmentScenario;
-      props.onLoad(scenario);
+      props.onLoad(data);
     });
   }
 

web/src/components/CaseBuilder/ThermalUnits.tsx

@@ -51,13 +51,13 @@ export const ThermalUnitsColumnSpec: ColumnSpec[] = [
     title: "Production cost curve (MW)",
     type: "number[N]",
     length: 10,
-    width: 75,
+    width: 80,
   },
   {
     title: "Production cost curve ($)",
     type: "number[N]",
     length: 10,
-    width: 75,
+    width: 80,
   },
   {
     title: "Startup costs ($)",
@@ -83,22 +83,22 @@ export const ThermalUnitsColumnSpec: ColumnSpec[] = [
   },
   {
     title: "Ramp up limit (MW)",
-    type: "number",
+    type: "number?",
     width: 100,
   },
   {
     title: "Ramp down limit (MW)",
-    type: "number",
+    type: "number?",
     width: 100,
   },
   {
     title: "Startup limit (MW)",
-    type: "number",
+    type: "number?",
     width: 80,
   },
   {
     title: "Shutdown limit (MW)",
-    type: "number",
+    type: "number?",
     width: 100,
   },
   {

web/src/components/CaseBuilder/TransmissionLines.tsx

@@ -55,12 +55,12 @@ export const TransmissionLinesColumnSpec: ColumnSpec[] = [
   },
   {
     title: "Normal flow limit (MW)",
-    type: "number",
+    type: "number?",
     width: 60,
   },
   {
     title: "Emergency flow limit (MW)",
-    type: "number",
+    type: "number?",
     width: 60,
   },
   {

web/src/components/Common/Forms/DataTable.tsx

@@ -17,7 +17,14 @@ import { UnitCommitmentScenario } from "../../../core/Data/types";
 
 export interface ColumnSpec {
   title: string;
-  type: "string" | "number" | "number[N]" | "number[T]" | "busRef" | "boolean";
+  type:
+    | "string"
+    | "number"
+    | "number?"
+    | "number[N]"
+    | "number[T]"
+    | "busRef"
+    | "boolean";
   length?: number;
   width: number;
 }
@@ -53,6 +60,7 @@ export const generateTableColumns = (
         });
         break;
       case "number":
+      case "number?":
         columns.push({
           ...columnsCommonAttrs,
           title: spec.title,
@@ -118,6 +126,7 @@ export const generateTableData = (
       switch (spec.type) {
         case "string":
         case "number":
+        case "number?":
         case "boolean":
         case "busRef":
           entry[spec.title] = entryData[spec.title];
@@ -285,7 +294,7 @@ export const parseCsv = (
 
 export const floatFormatter = (cell: CellComponent) => {
   const v = cell.getValue();
-  if (v === "") {
+  if (v === "" || v === null) {
     return "—";
   } else {
     return parseFloat(cell.getValue()).toLocaleString("en-US", {

web/src/core/Data/fixtures.tsx

@@ -120,8 +120,8 @@ export const TEST_SCENARIO: UnitCommitmentScenario = {
       "Source bus": "b1",
       "Target bus": "b2",
       "Susceptance (S)": 29.49686,
-      "Normal flow limit (MW)": 15000.0,
-      "Emergency flow limit (MW)": 20000.0,
+      "Normal flow limit (MW)": null,
+      "Emergency flow limit (MW)": null,
       "Flow limit penalty ($/MW)": 5000.0,
     },
   },

web/src/core/Data/schema.ts

@@ -97,15 +97,18 @@ export const schema = {
           },
           "Susceptance (S)": {
             type: "number",
-            minimum: 0,
           },
           "Normal flow limit (MW)": {
             type: "number",
             minimum: 0,
+            nullable: true,
+            default: null,
           },
           "Emergency flow limit (MW)": {
             type: "number",
             minimum: 0,
+            nullable: true,
+            default: null,
           },
           "Flow limit penalty ($/MW)": {
             type: "number",
@@ -254,18 +257,26 @@ export const schema = {
             "Ramp up limit (MW)": {
               type: "number",
               minimum: 0,
+              nullable: true,
+              default: null,
             },
             "Ramp down limit (MW)": {
               type: "number",
               minimum: 0,
+              nullable: true,
+              default: null,
             },
             "Startup limit (MW)": {
               type: "number",
               minimum: 0,
+              nullable: true,
+              default: null,
             },
             "Shutdown limit (MW)": {
               type: "number",
               minimum: 0,
+              nullable: true,
+              default: null,
             },
             "Initial status (h)": {
               type: "integer",

web/src/core/Data/types.tsx

@@ -25,10 +25,10 @@ export interface ThermalUnit {
   "Production cost curve ($)": number[];
   "Startup costs ($)": number[];
   "Startup delays (h)": number[];
-  "Ramp up limit (MW)": number | "";
-  "Ramp down limit (MW)": number | "";
-  "Startup limit (MW)": number | "";
-  "Shutdown limit (MW)": number | "";
+  "Ramp up limit (MW)": number | null;
+  "Ramp down limit (MW)": number | null;
+  "Startup limit (MW)": number | null;
+  "Shutdown limit (MW)": number | null;
   "Minimum downtime (h)": number;
   "Minimum uptime (h)": number;
   "Initial status (h)": number;
@@ -40,8 +40,8 @@ export interface TransmissionLine {
   "Source bus": string;
   "Target bus": string;
   "Susceptance (S)": number;
-  "Normal flow limit (MW)": number;
-  "Emergency flow limit (MW)": number;
+  "Normal flow limit (MW)": number | null;
+  "Emergency flow limit (MW)": number | null;
   "Flow limit penalty ($/MW)": number;
 }
 

web/src/core/Operations/commonOps.ts

@@ -43,6 +43,9 @@ export const generateUniqueName = (container: any, prefix: string): string => {
 export const parseNumber = (
   valueStr: string,
 ): [number, ValidationError | null] => {
+  if (valueStr === "") {
+    return [0, { message: "Field must not be blank" }];
+  }
   const valueFloat = parseFloat(valueStr);
   if (isNaN(valueFloat)) {
     return [0, { message: `"${valueStr}" is not a valid number` }];
@@ -51,6 +54,13 @@ export const parseNumber = (
   }
 };
 
+export const parseNullableNumber = (
+  valueStr: string,
+): [number | null, ValidationError | null] => {
+  if (valueStr === "") return [null, null];
+  return parseNumber(valueStr);
+};
+
 export const parseBool = (
   valueStr: string,
 ): [boolean, ValidationError | null] => {
@@ -93,9 +103,12 @@ export const changeNumberData = (
   field: string,
   newValueStr: string,
   container: { [key: string]: any },
+  nullable: boolean = false,
 ): [{ [key: string]: any }, ValidationError | null] => {
   // Parse value
-  const [newValueFloat, err] = parseNumber(newValueStr);
+  const [newValueFloat, err] = nullable
+    ? parseNullableNumber(newValueStr)
+    : parseNumber(newValueStr);
   if (err) return [container, err];
 
   // Build the new object
@@ -211,6 +224,8 @@ export const changeData = (
         return changeBusRefData(fieldName, newValueStr, container, scenario);
       case "number":
         return changeNumberData(fieldName, newValueStr, container);
+      case "number?":
+        return changeNumberData(fieldName, newValueStr, container, true);
       case "number[T]":
         return changeNumberVecTData(
           fieldName,

web/src/core/Operations/generatorOps.ts

@@ -61,10 +61,10 @@ export const createThermalUnit = (
           "Production cost curve ($)": [0, 10],
           "Startup costs ($)": [0],
           "Startup delays (h)": [1],
-          "Ramp up limit (MW)": "",
-          "Ramp down limit (MW)": "",
-          "Startup limit (MW)": "",
-          "Shutdown limit (MW)": "",
+          "Ramp up limit (MW)": null,
+          "Ramp down limit (MW)": null,
+          "Startup limit (MW)": null,
+          "Shutdown limit (MW)": null,
           "Minimum downtime (h)": 1,
           "Minimum uptime (h)": 1,
           "Initial status (h)": -24,

web/src/core/Operations/preprocessing.ts

@@ -1,25 +1,35 @@
-// @ts-nocheck
-
 /*
  * UnitCommitment.jl: Optimization Package for Security-Constrained Unit Commitment
  * Copyright (C) 2020-2025, UChicago Argonne, LLC. All rights reserved.
  * Released under the modified BSD license. See COPYING.md for more details.
  */
 
-import { validate } from "../Data/validate";
+import { validate, ValidationError } from "../Data/validate";
+import { UnitCommitmentScenario } from "../Data/types";
+import { migrate } from "../Data/migrate";
 
-export const preprocess = (data) => {
+export const preprocess = (
+  data: any,
+): [UnitCommitmentScenario | null, ValidationError | null] => {
   // Make a copy of the original data
   let result = JSON.parse(JSON.stringify(data));
 
+  // Run migration
+  migrate(result);
+
   // Run JSON validation and assign default values
   if (!validate(result)) {
     console.error(validate.errors);
-    throw Error("Invalid JSON");
+    return [
+      null,
+      { message: "Invalid JSON file. See console for more details." },
+    ];
   }
 
   // Expand scalars into arrays
+  // @ts-ignore
   const timeHorizon = result["Parameters"]["Time horizon (h)"];
+  // @ts-ignore
   const timeStep = result["Parameters"]["Time step (min)"];
   const T = (timeHorizon * 60) / timeStep;
   for (const busName in result["Buses"]) {
@@ -30,5 +40,7 @@ export const preprocess = (data) => {
       busData["Load (MW)"] = Array(T).fill(busLoad);
     }
   }
-  return result;
+
+  const scenario = result as unknown as UnitCommitmentScenario;
+  return [scenario, null];
 };