From fcb960533823090eff6fae936ffa0058db65ff88 Mon Sep 17 00:00:00 2001
From: Iaroslav Postovalov <postovalovya@gmail.com>
Date: Thu, 13 May 2021 22:59:35 +0700
Subject: [PATCH] Special rendering of Quaternion #330

---
 .../space/kscience/kmath/complex/Complex.kt   |  2 +-
 .../kscience/kmath/jupyter/KMathJupyter.kt    | 24 ++++++++++++-------
 2 files changed, 17 insertions(+), 9 deletions(-)

diff --git a/kmath-complex/src/commonMain/kotlin/space/kscience/kmath/complex/Complex.kt b/kmath-complex/src/commonMain/kotlin/space/kscience/kmath/complex/Complex.kt
index 8e28337f6..a96d046c9 100644
--- a/kmath-complex/src/commonMain/kotlin/space/kscience/kmath/complex/Complex.kt
+++ b/kmath-complex/src/commonMain/kotlin/space/kscience/kmath/complex/Complex.kt
@@ -187,7 +187,7 @@ public data class Complex(val re: Double, val im: Double) {
     public constructor(re: Number, im: Number) : this(re.toDouble(), im.toDouble())
     public constructor(re: Number) : this(re.toDouble(), 0.0)
 
-    public override fun toString(): String = "($re + i*$im)"
+    public override fun toString(): String = "($re + i * $im)"
 
     public companion object : MemorySpec<Complex> {
         public override val objectSize: Int
diff --git a/kmath-jupyter/src/main/kotlin/space/kscience/kmath/jupyter/KMathJupyter.kt b/kmath-jupyter/src/main/kotlin/space/kscience/kmath/jupyter/KMathJupyter.kt
index f3d553f2e..e3767e13c 100644
--- a/kmath-jupyter/src/main/kotlin/space/kscience/kmath/jupyter/KMathJupyter.kt
+++ b/kmath-jupyter/src/main/kotlin/space/kscience/kmath/jupyter/KMathJupyter.kt
@@ -12,18 +12,19 @@ import space.kscience.kmath.ast.rendering.FeaturedMathRendererWithPostProcess
 import space.kscience.kmath.ast.rendering.MathMLSyntaxRenderer
 import space.kscience.kmath.ast.rendering.renderWithStringBuilder
 import space.kscience.kmath.complex.Complex
+import space.kscience.kmath.complex.Quaternion
 import space.kscience.kmath.expressions.MST
+import space.kscience.kmath.expressions.MstRing
 import space.kscience.kmath.misc.PerformancePitfall
 import space.kscience.kmath.nd.Structure2D
-import space.kscience.kmath.operations.GroupOperations
-import space.kscience.kmath.operations.RingOperations
+import space.kscience.kmath.operations.invoke
 import space.kscience.kmath.structures.Buffer
 import space.kscience.kmath.structures.asSequence
 
 /**
  * A function for conversion of number to MST for pretty print
  */
-public fun Number.toMst(): MST.Numeric =  MST.Numeric(this)
+public fun Number.toMst(): MST.Numeric = MST.Numeric(this)
 
 @JupyterLibrary
 internal class KMathJupyter : JupyterIntegration() {
@@ -121,11 +122,18 @@ internal class KMathJupyter : JupyterIntegration() {
         }
 
         render<Complex> {
-            MST.Binary(
-                operation = GroupOperations.PLUS_OPERATION,
-                left = MST.Numeric(it.re),
-                right = MST.Binary(RingOperations.TIMES_OPERATION, MST.Numeric(it.im), MST.Symbolic("i")),
-            ).toDisplayResult()
+            MstRing {
+                number(it.re) + number(it.im) * bindSymbol("i")
+            }.toDisplayResult()
+        }
+
+        render<Quaternion> {
+            MstRing {
+                number(it.w) +
+                        number(it.x) * bindSymbol("i") +
+                        number(it.x) * bindSymbol("j") +
+                        number(it.x) * bindSymbol("k")
+            }.toDisplayResult()
         }
     }
 }