commit e223aa575125109459cbc04e5a57c0ac5b1e480c
Author: Michael Halls-Moore <mike@quarkgluon.com>
Date:   Tue Jan 27 18:29:27 2015 +0000

    First commit

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..11ef5d2
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,28 @@
+*~
+*.py[co]
+
+# Packages
+*.egg
+*.egg-info
+dist
+build
+eggs
+parts
+bin
+var
+sdist
+develop-eggs
+.installed.cfg
+
+# Installer logs
+pip-log.txt
+
+# Unit test / coverage reports
+.coverage
+.tox
+
+#Translations
+*.mo
+
+#Mr Developer
+.mr.developer.cfg
diff --git a/portfolio/__init__.py b/portfolio/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/portfolio/portfolio.py b/portfolio/portfolio.py
new file mode 100644
index 0000000..f279ff6
--- /dev/null
+++ b/portfolio/portfolio.py
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+from copy import deepcopy
+
+from position import Position
+
+
+class Portfolio(object):
+    def __init__(
+        self, ticker, base="GBP", leverage=20, 
+        equity=100000.0, risk_per_trade=0.02
+    ):
+        self.ticker = ticker
+        self.base = base
+        self.leverage = leverage
+        self.equity = equity
+        self.balance = deepcopy(self.equity)
+        self.risk_per_trade = risk_per_trade
+        self.trade_units = self.calc_risk_position_size()
+        self.positions = {}
+
+    def calc_risk_position_size(self):
+        return self.equity * self.risk_per_trade
+
+    def add_new_position(
+        self, side, market, units, exposure,
+        add_price, remove_price
+    ):
+        ps = Position(
+            side, market, units, exposure,
+            add_price, remove_price
+        )
+        self.positions[market] = ps
+
+    def add_position_units(
+        self, market, units, exposure, 
+        add_price, remove_price
+    ):
+        if market not in self.positions:
+            return False
+        else:
+            ps = self.positions[market]
+            new_total_units = ps.units + units
+            new_total_cost = ps.avg_price*ps.units + add_price*units
+            ps.exposure += exposure
+            ps.avg_price = new_total_cost/new_total_units
+            ps.units = new_total_units
+            ps.update_position_price(remove_price)
+            return True
+
+    def remove_position_units(
+        self, market, units, remove_price
+    ):
+        if market not in self.positions:
+            return False
+        else:
+            ps = self.positions[market]
+            ps.units -= units
+            ps.exposure -= float(units)
+            ps.update_position_price(self, remove_price)
+            pnl = ps.profit_base
+            self.balance += pnl
+            return True
+
+    def close_position(
+        self, market, remove_price
+    ):
+        if market not in self.positions:
+            return False
+        else:
+            ps = self.positions[market]
+            ps.update_position_price(self, remove_price)
+            pnl = ps.profit_base
+            self.balance += pnl
+            del[self.positions[market]]
+            return True
+
+    def execute_signal(self, signal_event):
+        side = signal_event.side
+        market = signal_event.market
+        units = self.risk_per_trade
+
+        # Check side for correct bid/ask prices
+        if side == "LONG":
+            add_price = self.ticker.cur_ask
+            remove_price = self.ticker.cur_bid
+        else:
+            add_price = self.ticker.cur_bid
+            remove_price = self.ticker.cur_ask
+        exposure = float(units)
+
+        # If there is no position, create one
+        if market not in self.positions:
+            self.add_new_position(
+                side, market, units, exposure,
+                add_price, remove_price
+            )
+        # If a position exists add or remove units
+        else:
+            # Check if the sides equal
+            if side == ps[market].side:
+                # Add to the position
+                add_position_units(
+                    market, units, exposure,
+                    add_price, remove_price
+                )
+            else:
+                # Check if the units close out the position
+                if units == ps.units:
+                    # Close the position
+                    self.close_position(market, remove_price)
+                elif units < ps.units:
+                    # Remove from the position
+                    self.remove_position_units(
+                        market, units, remove_price
+                    )
+                else: # units > ps.units
+                    # Close the position and add a new one with
+                    # additional units of opposite side
+                    new_units = units - ps.units
+                    self.close_position(market, remove_price)
+                    
+                    if side == "LONG":
+                        new_side = "SHORT"
+                    else:
+                        new_side = "LONG"
+                    new_exposure = float(units)
+                    self.add_new_position(
+                        new_side, market, new_units, 
+                        new_exposure, add_price, remove_price
+                    )
diff --git a/portfolio/portfolio_test.py b/portfolio/portfolio_test.py
new file mode 100644
index 0000000..f06e5da
--- /dev/null
+++ b/portfolio/portfolio_test.py
@@ -0,0 +1,68 @@
+import unittest
+
+#from position import Position
+from portfolio import Portfolio
+
+
+class TestPortfolio(unittest.TestCase):
+    def setUp(self):
+        base = "GBP"
+        leverage = 20
+        equity = 100000.0
+        risk_per_trade = 0.02
+        ticker = {}
+        self.port = Portfolio(
+            ticker, base=base, leverage=leverage, 
+            equity=equity, risk_per_trade=risk_per_trade
+        )
+
+    def test_add_position(self):
+        side = "LONG"
+        market = "GBP/USD"
+        units = 2000
+        exposure = float(units)
+        add_price = 1.51819
+        remove_price = 1.51770
+
+        self.port.add_new_position(
+            side, market, units, exposure,
+            add_price, remove_price
+        )
+        ps = self.port.positions[market]
+
+        self.assertEquals(ps.side, side)
+        self.assertEquals(ps.market, market)
+        self.assertEquals(ps.units, units)
+        self.assertEquals(ps.exposure, exposure)
+        self.assertEquals(ps.avg_price, add_price)
+        self.assertEquals(ps.cur_price, remove_price)
+
+    def test_add_position_units(self):
+        side = "LONG"
+        units = 2000
+        exposure = float(units)
+        add_price = 1.51928
+        remove_price = 1.51878
+
+        # Test for no position
+        market = "EUR/USD"
+        apu = self.port.add_position_units(
+            market, units, exposure,
+            add_price, remove_price
+        )
+        self.assertFalse(apu)
+
+        # Test for real position
+        market = "GBP/USD"
+        apu = self.port.add_position_units(
+            market, units, exposure,
+            add_price, remove_price
+        )
+        self.assertTrue(apu)
+        ps = self.port.positions[market]
+
+        self.assertAlmostEqual(ps.avg_price, 1.518735)
+
+
+if __name__ == "__main__":
+    unittest.main()
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diff --git a/portfolio/position.py b/portfolio/position.py
new file mode 100644
index 0000000..21728e9
--- /dev/null
+++ b/portfolio/position.py
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+class Position(object):
+    def __init__(
+        self, side, market, units, 
+        exposure, avg_price, cur_price
+    ):
+        self.side = side
+        self.market = market
+        self.units = units
+        self.exposure = exposure
+        self.avg_price = avg_price
+        self.cur_price = cur_price
+        self.profit_base = self.calculate_profit_base()
+        self.profit_perc = self.calculate_profit_perc()
+
+    def calculate_pips(self):
+        mult = 1.0
+        if self.side == "SHORT":
+            mult = -1.0
+        return mult * (self.cur_price - self.avg_price)
+
+    def calculate_profit_base(self):
+        pips = self.calculate_pips()
+        return pips * self.exposure / self.cur_price
+
+    def calculate_profit_perc(self):
+        return self.profit_base / self.exposure * 100.0
+
+    def update_position_price(self, cur_price):
+        self.cur_price = cur_price
+        self.profit_base = self.calculate_profit_base()
+        self.profit_perc = self.calculate_profit_perc()
+
diff --git a/portfolio/position_test.py b/portfolio/position_test.py
new file mode 100644
index 0000000..0954868
--- /dev/null
+++ b/portfolio/position_test.py
@@ -0,0 +1,59 @@
+import unittest
+
+from position import Position
+
+
+class TestLongGBPUSDPosition(unittest.TestCase):
+    def setUp(self):
+        side = "LONG"
+        market = "GBP/USD"
+        units = 2000
+        exposure = 2000.0
+        avg_price = 1.51819
+        cur_price = 1.51770
+        self.position = Position(
+            side, market, units, exposure,
+            avg_price, cur_price
+        )
+
+    def test_calculate_pips(self):
+        pos_pips = self.position.calculate_pips()
+        self.assertAlmostEqual(pos_pips, -0.00049)
+
+    def test_calculate_profit_base(self):
+        profit_base = self.position.calculate_profit_base()
+        self.assertAlmostEqual(profit_base, -0.6457139)
+
+    def test_calculate_profit_perc(self):
+        profit_perc = self.position.calculate_profit_perc()
+        self.assertAlmostEqual(profit_perc, -0.032285695)
+
+
+class TestShortGBPUSDPosition(unittest.TestCase):
+    def setUp(self):
+        side = "SHORT"
+        market = "GBP/USD"
+        units = 2000
+        exposure = 2000.0
+        avg_price = 1.51819
+        cur_price = 1.51770
+        self.position = Position(
+            side, market, units, exposure,
+            avg_price, cur_price
+        )
+
+    def test_calculate_pips(self):
+        pos_pips = self.position.calculate_pips()
+        self.assertAlmostEqual(pos_pips, 0.00049)
+
+    def test_calculate_profit_base(self):
+        profit_base = self.position.calculate_profit_base()
+        self.assertAlmostEqual(profit_base, 0.6457139)
+
+    def test_calculate_profit_perc(self):
+        profit_perc = self.position.calculate_profit_perc()
+        self.assertAlmostEqual(profit_perc, 0.032285695)
+
+
+if __name__ == "__main__":
+    unittest.main()
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