From a3a7aeddc93dec1a2c73e07f7226c07a415c11f3 Mon Sep 17 00:00:00 2001
From: danieljankowski <daniel.jankowski@rub.de>
Date: Mon, 18 Feb 2019 17:03:21 +0100
Subject: [PATCH] Added: gaussian elimination
---
algebra.go | 1 +
gaussian.go | 32 ++++++++++++++++++++++++++++++++
gaussian_test.go | 28 ++++++++++++++++++++++++++++
matrix.go | 1 +
4 files changed, 62 insertions(+)
create mode 100644 gaussian.go
create mode 100644 gaussian_test.go
diff --git a/algebra.go b/algebra.go
index 830fccf..cf7df57 100644
--- a/algebra.go
+++ b/algebra.go
@@ -1,3 +1,4 @@
+// Package gomatrix Is a go package for scientific operations with matrices in F2.
package gomatrix
import (
diff --git a/gaussian.go b/gaussian.go
new file mode 100644
index 0000000..b50df76
--- /dev/null
+++ b/gaussian.go
@@ -0,0 +1,32 @@
+// Package gomatrix Is a go package for scientific operations with matrices in F2.
+package gomatrix
+
+// GaussianElimination converts the matrix to an echelon form
+//
+// This function applies the gaussian elemination to the matrix in order to
+// create an echelon form.
+func (f *F2) GaussianElimination() {
+ // iterate through all possible pivot bits
+ for pivotBit := 0; pivotBit < f.M; pivotBit++ {
+ // iterate through the rows
+ for rowCounter := 0; rowCounter < f.N; rowCounter++ {
+ // if the pivotbit of this row is 0...
+ if f.Rows[rowCounter].Bit(pivotBit) == uint(0) {
+ // ...check the next row
+ continue
+ }
+
+ // if the row with a valid pivot bit is not the first row...
+ if pivotBit != rowCounter {
+ // ...swap it with first one
+ f.SwapRows(pivotBit, rowCounter)
+ }
+
+ // iterate through all other rows except the first one
+ for rr := pivotBit + 1; rr < f.N; rr++ {
+ // substract the 1 from all other rows with the pivotBit
+ f.Rows[rr].Xor(f.Rows[rr], f.Rows[pivotBit])
+ }
+ }
+ }
+}
diff --git a/gaussian_test.go b/gaussian_test.go
new file mode 100644
index 0000000..bb2a4f4
--- /dev/null
+++ b/gaussian_test.go
@@ -0,0 +1,28 @@
+// Package gomatrix Is a go package for scientific operations with matrices in F2.
+package gomatrix
+
+import (
+ "math/big"
+ "testing"
+
+ "github.com/stretchr/testify/assert"
+)
+
+func TestGaussianElimination(t *testing.T) {
+ tests := []struct {
+ description string
+ matrixA *F2
+ expectedMatrix *F2
+ }{
+ {
+ matrixA: NewF2(2, 2).Set([]*big.Int{big.NewInt(2), big.NewInt(1)}),
+ expectedMatrix: NewF2(2, 2).Set([]*big.Int{big.NewInt(1), big.NewInt(3)}),
+ },
+ }
+
+ for _, test := range tests {
+ test.matrixA.GaussianElimination()
+
+ assert.True(t, test.matrixA.IsEqual(test.expectedMatrix))
+ }
+}
diff --git a/matrix.go b/matrix.go
index eb32b70..2ccc137 100644
--- a/matrix.go
+++ b/matrix.go
@@ -1,3 +1,4 @@
+// Package gomatrix Is a go package for scientific operations with matrices in F2.
package gomatrix
import (
--
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