Add option to export simulation state as JSON

- Define Gate.processedStatsToJsonFunc
- Tranpose density matrix data for density matrix display
- Add processedStatsToJsonFunc to most displays
- Track most recent CircuitStats in main
- Added "to readable json" methods to Matrix and CircuitStats

html/export.partial.html

@@ -13,11 +13,19 @@
             <button tabindex="102" id="download-offline-copy-button" style="width:600px; height:60px;">Download ...</button>
         </div>
 
-        <strong>JSON</strong> - Parsable representation of current circuit.
+        <strong>Circuit JSON</strong> - Parsable representation of current circuit.
         <div style="margin: 10px 0 0 20px;">
             <button tabindex="103" id="export-json-copy-button">Copy to Clipboard</button>&nbsp;&nbsp;<span id="export-json-copy-result"></span>
             <br>
             <pre tabindex="104" id="export-circuit-json-pre" style="overflow:auto; max-width:600px; max-height:60px; border: 1px solid black; padding:5px; margin:2px;"></pre>
         </div>
+
+        <br>
+        <strong>Simulation Data JSON</strong> - Output amplitudes, detector results, display data, etc.
+        <div style="margin: 10px 0 0 20px;">
+            <button tabindex="103" id="export-amplitudes-button">Generate and Copy to Clipboard</button>&nbsp;<span id="export-amplitudes-result"></span>
+            <br>
+            <pre tabindex="105" id="export-amplitudes-pre" style="overflow:auto; max-width:600px; max-height:60px; border: 1px solid black; padding:5px; margin:2px;"></pre>
+        </div>
     </div>
 </div>

src/circuit/CircuitStats.js

@@ -18,7 +18,7 @@ import {CircuitShaders} from "src/circuit/CircuitShaders.js"
 import {KetTextureUtil} from "src/circuit/KetTextureUtil.js"
 import {Controls} from "src/circuit/Controls.js"
 import {DetailedError} from "src/base/DetailedError.js"
-import {Matrix} from "src/math/Matrix.js"
+import {Matrix, complexVectorToReadableJson} from "src/math/Matrix.js"
 import {Shaders} from "src/webgl/Shaders.js"
 import {Serializer} from "src/circuit/Serializer.js"
 import {Util} from "src/base/Util.js"
@@ -108,6 +108,48 @@ class CircuitStats {
         return this._qubitDensities[col][wireIndex];
     }
 
+    /**
+     * Converts the circuit stats into an exportable JSON object.
+     * @returns {!object}
+     */
+    toReadableJson() {
+        return {
+            output_amplitudes: complexVectorToReadableJson(this.finalState.getColumn(0)),
+            time_parameter: this.time,
+            circuit: Serializer.toJson(this.circuitDefinition),
+            chance_of_surviving_to_each_column: this._survivalRates,
+            computed_bloch_vectors_by_column_then_wire: this._qubitDensities.map(
+                col => col.map(singleQubitDensityMatrixToReadableJson)
+            ),
+            displays: this._customStatsToReadableJson()
+        };
+    }
+
+    _customStatsToReadableJson() {
+        let result = [];
+        for (let [key, data] of this._customStatsProcessed.entries()) {
+            let [col, row] = key.split(':');
+            row = parseInt(row);
+            col = parseInt(col);
+            let gate = this.circuitDefinition.columns[col].gates[row];
+            if (gate.processedStatsToJsonFunc !== undefined) {
+                data = gate.processedStatsToJsonFunc(data);
+            }
+            result.push({
+                location: {
+                    wire: row,
+                    column: col,
+                },
+                type: {
+                    serialized_id: gate.serializedId,
+                    name: gate.name,
+                },
+                data
+            });
+        }
+        return result;
+    }
+
     /**
      * Determines how often the circuit evaluation survives to the given column, without being post-selected out.
      *
@@ -341,6 +383,19 @@ class CircuitStats {
     }
 }
 
+/**
+ * @param {!Matrix} matrix
+ */
+function singleQubitDensityMatrixToReadableJson(matrix) {
+    if (matrix.hasNaN()) {
+        return null;
+    }
+    let [x, y, z] = matrix.qubitDensityMatrixToBlochVector();
+    x *= -1;
+    z *= -1;
+    return {x, y, z};
+}
+
 CircuitStats.EMPTY = CircuitStats.withNanDataFromCircuitAtTime(CircuitDefinition.EMPTY, 0);
 
 export {CircuitStats}

src/circuit/Gate.js

@@ -71,6 +71,11 @@ class Gate {
          * @type {undefined|!function(!Float32Array, !CircuitDefinition, !int, !int) : *}
          */
         this.customStatPostProcesser = undefined;
+        /**
+         * Returns a json form of the custom-stat data, used when exporting it.
+         * @type {undefined|!function(data: *) : *}
+         */
+        this.processedStatsToJsonFunc = undefined;
         /** @type {!Array.<!Gate>} A list of size variants of this gate.*/
         this.gateFamily = [this];
 
@@ -262,6 +267,7 @@ class Gate {
         g.customAfterOperation = this.customAfterOperation;
         g.customStatTexturesMaker = this.customStatTexturesMaker;
         g.customStatPostProcesser = this.customStatPostProcesser;
+        g.processedStatsToJsonFunc = this.processedStatsToJsonFunc;
         g.width = this.width;
         g.height = this.height;
         g.isSingleQubitDisplay = this.isSingleQubitDisplay;
@@ -926,6 +932,16 @@ class GateBuilder {
         return this;
     }
 
+    /**
+     * Specifies how to convert custom stats data into json when exporting.
+     * @param {undefined|!function(data: *) : *} jsonFunc
+     * @returns {!GateBuilder}
+     */
+    setProcessedStatsToJsonFunc(jsonFunc) {
+        this.gate.processedStatsToJsonFunc = jsonFunc;
+        return this;
+    }
+
     /**
      * @param {*} tag
      * @returns {!GateBuilder}

src/draw/MathPainter.js

@@ -551,7 +551,7 @@ class MathPainter {
         let traceCouplingsWith = cellTraceFunc => painter.trace(trace => {
             for (let row = 0; row < numRows; row++) {
                 for (let col = 0; col < numCols; col++) {
-                    let k = (row + col * numRows) * 2;
+                    let k = (row * numCols + col) * 2;
                     cellTraceFunc(
                         trace,
                         buf[k],
@@ -625,8 +625,8 @@ class MathPainter {
                 `Probability of |${Util.bin(c, n)}⟩` :
                 `Coupling of |${Util.bin(r, n)}⟩ to ⟨${Util.bin(c, n)}|`,
             (c, r, v) => c === r ?
-                (matrix.cell(r, c).real*100).toFixed(4) + "%" :
-                matrix.cell(r, c).toString(new Format(false, 0, 6, ", ")));
+                (matrix.cell(c, r).real*100).toFixed(4) + "%" :
+                matrix.cell(c, r).toString(new Format(false, 0, 6, ", ")));
     }
 }
 

src/gates/AmplitudeDisplay.js

@@ -12,14 +12,15 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+import {Complex} from "src/math/Complex.js"
 import {Config} from "src/Config.js"
 import {CircuitShaders} from "src/circuit/CircuitShaders.js"
 import {Gate} from "src/circuit/Gate.js"
 import {GatePainting} from "src/draw/GatePainting.js"
 import {GateShaders} from "src/circuit/GateShaders.js"
 import {Format} from "src/base/Format.js"
 import {MathPainter} from "src/draw/MathPainter.js"
-import {Matrix} from "src/math/Matrix.js"
+import {Matrix, complexVectorToReadableJson, realVectorToReadableJson} from "src/math/Matrix.js"
 import {Point} from "src/math/Point.js"
 import {Util} from "src/base/Util.js"
 import {WglArg} from "src/webgl/WglArg.js"
@@ -417,6 +418,30 @@ function paintErrorIfPresent(args, isIncoherent) {
     }
 }
 
+/**
+ * @param customStats
+ */
+function customStatsToJsonData(customStats) {
+    let {probabilities, superposition, phaseLockIndex} = customStats;
+    let result = {
+        coherence_measure: superposition !== undefined ? 1 : 0,
+        superposition_phase_locked_state_index: phaseLockIndex === undefined ? null : phaseLockIndex,
+        probabilities: null,
+        amplitudes: null,
+
+    };
+    if (probabilities !== undefined) {
+        let n = probabilities._width * probabilities._height;
+        result['probabilities'] = realVectorToReadableJson(
+            new Matrix(1, n, probabilities._buffer).getColumn(0).map(e => Math.pow(Complex.realPartOf(e), 2)));
+    }
+    if (superposition !== undefined) {
+        let n = superposition._width * superposition._height;
+        result['superposition'] = complexVectorToReadableJson(new Matrix(1, n, superposition._buffer).getColumn(0));
+    }
+    return result;
+}
+
 let AmplitudeDisplayFamily = Gate.buildFamily(1, 16, (span, builder) => builder.
     setSerializedId("Amps" + span).
     setSymbol("Amps").
@@ -428,6 +453,7 @@ let AmplitudeDisplayFamily = Gate.buildFamily(1, 16, (span, builder) => builder.
     setStatTexturesMaker(ctx =>
         amplitudeDisplayStatTextures(ctx.stateTrader.currentTexture, ctx.controls, ctx.row, span)).
     setStatPixelDataPostProcessor((val, def) => processOutputs(span, val, def)).
+    setProcessedStatsToJsonFunc(customStatsToJsonData).
     setDrawer(AMPLITUDE_DRAWER_FROM_CUSTOM_STATS));
 
 export {

src/gates/DensityMatrixDisplay.js

@@ -144,7 +144,7 @@ function densityPixelsToMatrix(pixels, circuitDefinition, col, row) {
     }
 
     let isMeasuredMask = circuitDefinition.colIsMeasuredMask(col) >> row;
-    return decohereMeasuredBitsInDensityMatrix(new Matrix(d, d, pixels), isMeasuredMask);
+    return decohereMeasuredBitsInDensityMatrix(new Matrix(d, d, pixels), isMeasuredMask).transpose();
 }
 
 /**
@@ -186,6 +186,9 @@ function largeDensityMatrixDisplayMaker(span, builder) {
         setSerializedId("Density" + span).
         setWidth(span).
         setDrawer(DENSITY_MATRIX_DRAWER_FROM_CUSTOM_STATS).
+        setProcessedStatsToJsonFunc(data => {
+            return {density_matrix: data.toReadableJson()};
+        }).
         setStatTexturesMaker(ctx => densityDisplayStatTexture(
             ctx.stateTrader.currentTexture, ctx.wireCount, ctx.controls, ctx.row, span)).
         setStatPixelDataPostProcessor(densityPixelsToMatrix);

src/gates/ProbabilityDisplay.js

@@ -12,6 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+import {Complex} from "src/math/Complex.js"
 import {Config} from "src/Config.js"
 import {Gate} from "src/circuit/Gate.js"
 import {GatePainting} from "src/draw/GatePainting.js"
@@ -20,6 +21,7 @@ import {MathPainter} from "src/draw/MathPainter.js"
 import {Matrix} from "src/math/Matrix.js"
 import {Point} from "src/math/Point.js"
 import {Rect} from "src/math/Rect.js"
+import {Seq} from "src/base/Seq.js"
 import {Shaders} from "src/webgl/Shaders.js"
 import {Util} from "src/base/Util.js"
 import {WglConfiguredShader} from "src/webgl/WglConfiguredShader.js"
@@ -98,6 +100,20 @@ function probabilityPixelsToColumnVector(pixels, span) {
     return new Matrix(1, n, buf);
 }
 
+/**
+ * @param {!Matrix} data
+ * @returns {!{probabilities: !float[]}}
+ */
+function probabilityDataToJson(data) {
+    return {
+        probabilities: Seq.range(data.height()).map(k => Complex.realPartOf(data.cell(0, k))).toArray()
+    };
+}
+
+/**
+ * @param {!GateDrawParams} args
+ * @private
+ */
 function _paintMultiProbabilityDisplay_grid(args) {
     let {painter, rect: {x, y, w, h}} = args;
     let n = 1 << args.gate.height;
@@ -258,6 +274,7 @@ function multiChanceGateMaker(span, builder) {
         setStatTexturesMaker(ctx =>
             probabilityStatTexture(ctx.stateTrader.currentTexture, ctx.controlsTexture, ctx.row, span)).
         setStatPixelDataPostProcessor(pixels => probabilityPixelsToColumnVector(pixels, span)).
+        setProcessedStatsToJsonFunc(probabilityDataToJson).
         setDrawer(GatePainting.makeDisplayDrawer(paintMultiProbabilityDisplay));
 }
 
@@ -288,5 +305,6 @@ export {
     ProbabilityDisplayFamily,
     probabilityStatTexture,
     probabilityPixelsToColumnVector,
-    amplitudesToProbabilities
+    amplitudesToProbabilities,
+    probabilityDataToJson,
 };

src/gates/SampleDisplay.js

@@ -19,7 +19,11 @@ import {MathPainter} from "src/draw/MathPainter.js"
 import {Point} from "src/math/Point.js"
 import {Rect} from "src/math/Rect.js"
 import {Util} from "src/base/Util.js"
-import {probabilityStatTexture, probabilityPixelsToColumnVector} from "src/gates/ProbabilityDisplay.js"
+import {
+    probabilityStatTexture,
+    probabilityPixelsToColumnVector,
+    probabilityDataToJson
+} from "src/gates/ProbabilityDisplay.js"
 
 /**
  * @param {!GateDrawParams} args
@@ -106,6 +110,7 @@ let SampleDisplayFamily = Gate.buildFamily(1, 16, (span, builder) => builder.
         probabilityStatTexture(ctx.stateTrader.currentTexture, ctx.controlsTexture, ctx.row, span)).
     setStatPixelDataPostProcessor(e => probabilityPixelsToColumnVector(e, span)).
     promiseHasNoNetEffectOnStateVectorButStillRequiresDynamicRedraw().
+    setProcessedStatsToJsonFunc(probabilityDataToJson).
     setDrawer(GatePainting.makeDisplayDrawer(paintSampleDisplay)).
     setExtraDisableReasonFinder(args => args.isNested ? "can't\nnest\ndisplays\n(sorry)" : undefined));
 

src/main.js

@@ -19,6 +19,7 @@ hookErrorHandler();
 import {doDetectIssues} from "src/issues.js"
 doDetectIssues();
 
+import {CircuitStats} from "src/circuit/CircuitStats.js"
 import {CooldownThrottle} from "src/base/CooldownThrottle.js"
 import {Config} from "src/Config.js"
 import {DisplayedInspector} from "src/ui/DisplayedInspector.js"
@@ -79,6 +80,7 @@ const inspectorDiv = document.getElementById("inspectorDiv");
 /** @type {ObservableValue.<!DisplayedInspector>} */
 const displayed = new ObservableValue(
     DisplayedInspector.empty(new Rect(0, 0, canvas.clientWidth, canvas.clientHeight)));
+const mostRecentStats = new ObservableValue(CircuitStats.EMPTY);
 /** @type {!Revision} */
 let revision = Revision.startingAt(displayed.get().snapshot());
 
@@ -132,6 +134,7 @@ const redrawNow = () => {
 
     let shown = syncArea(displayed.get()).previewDrop();
     let stats = simulate(shown.displayedCircuit.circuitDefinition);
+    mostRecentStats.set(stats);
 
     let size = desiredCanvasSizeFor(shown);
     canvas.width = size.w;
@@ -275,7 +278,7 @@ canvasDiv.addEventListener('mouseleave', () => {
 
 let obsIsAnyOverlayShowing = new ObservableSource();
 initUrlCircuitSync(revision);
-initExports(revision, obsIsAnyOverlayShowing.observable());
+initExports(revision, mostRecentStats, obsIsAnyOverlayShowing.observable());
 initForge(revision, obsIsAnyOverlayShowing.observable());
 initUndoRedo(revision, obsIsAnyOverlayShowing.observable());
 initClear(revision, obsIsAnyOverlayShowing.observable());

src/math/Matrix.js

@@ -70,6 +70,13 @@ class Matrix {
         return this._buffer;
     }
 
+    /**
+     * Encodes the matrix into JSON that could easily be read by humans or processed by external programs.
+     * @returns {*}
+     */
+    toReadableJson() {
+        return seq(this.rows()).map(complexVectorToReadableJson).toArray();
+    }
     /**
      * @returns {!Array.<!Array.<Complex>>}
      */
@@ -1426,4 +1433,22 @@ Matrix.PAULI_Z = Matrix.square(1, 0, 0, -1);
  */
 Matrix.HADAMARD = Matrix.square(1, 1, 1, -1).times(Math.sqrt(0.5));
 
-export {Matrix}
+/**
+ * Encodes a complex vector into JSON that could easily be read by humans or processed by external programs.
+ * @param {!Iterable.<!Complex>} vector
+ * @returns {*}
+ */
+function complexVectorToReadableJson(vector) {
+    return seq(vector).map(e => {return {real: Complex.realPartOf(e), imag: Complex.imagPartOf(e)}; }).toArray();
+}
+
+/**
+ * Encodes a real vector into JSON that could easily be read by humans or processed by external programs.
+ * @param {!Iterable.<!Complex>} vector
+ * @returns {*}
+ */
+function realVectorToReadableJson(vector) {
+    return seq(vector).map(Complex.realPartOf).toArray();
+}
+
+export {Matrix, complexVectorToReadableJson, realVectorToReadableJson}