# Commits

committed acabc1b

Single variable solved

• Participants
• Parent commits 1139b63

# File ex1.py

`     return diff2.sum() / (2 * len(ys))`
` `
` `
`+def diff(i, j, theta, features, ys):`
`+    return ((features[i] * theta.T)[0, 0] - ys[i, 0]) * features[i, j]`
`+`
`+`
`+def step(j, theta, alpha, features, ys):`
`+    m = len(features)`
`+    mul = alpha/m`
`+`
`+    sumdiffs = sum(diff(i, j, theta, features, ys) for i in range(m))`
`+    return theta[0, j] - (mul * sumdiffs)`
`+`
`+`
` def linreg(features, ys):`
`     alpha = 0.01`
`     niter = 1500`
` `
`+    theta = np.matrix([0, 0])`
`+    for round in xrange(niter):`
`+        t0 = step(0, theta, alpha, features, ys)`
`+        t1 = step(1, theta, alpha, features, ys)`
`+        theta = np.matrix([t0, t1])`
` `
`-def plot():`
`+    return theta`
`+`
`+`
`+def plot(theta):`
`     data = list(load('ex1/ex1data1.txt'))`
`     xs = [p.item(0) for p in data]`
`     ys = [p.item(1) for p in data]`
` `
`+    t0 = theta[0,0]`
`+    t1 = theta[0,1]`
`+`
`+    tys = [(t0 + t1*x) for x in xs]`
`+`
`     fig = plt.figure()`
`     ax = fig.add_subplot(111)`
`     ax.plot(xs, ys, 'x', color='red')`
`+    ax.plot(xs, tys, color='blue')`
`     ax.set_xlabel('Population of City in 10,000s')`
`     ax.set_ylabel('Profit in \$10,000s')`
`     plt.show()`