Python/neural_network/perceptron.py
Christian Clauss 7ebe2b9593
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Co-authored-by: github-actions <${GITHUB_ACTOR}@users.noreply.github.com>
2020-04-13 02:10:21 +02:00

232 lines
6.6 KiB
Python

"""
Perceptron
w = w + N * (d(k) - y) * x(k)
Using perceptron network for oil analysis, with Measuring of 3 parameters
that represent chemical characteristics we can classify the oil, in p1 or p2
p1 = -1
p2 = 1
"""
import random
class Perceptron:
def __init__(self, sample, target, learning_rate=0.01, epoch_number=1000, bias=-1):
"""
Initializes a Perceptron network for oil analysis
:param sample: sample dataset of 3 parameters with shape [30,3]
:param target: variable for classification with two possible states -1 or 1
:param learning_rate: learning rate used in optimizing.
:param epoch_number: number of epochs to train network on.
:param bias: bias value for the network.
>>> p = Perceptron([], (0, 1, 2))
Traceback (most recent call last):
...
ValueError: Sample data can not be empty
>>> p = Perceptron(([0], 1, 2), [])
Traceback (most recent call last):
...
ValueError: Target data can not be empty
>>> p = Perceptron(([0], 1, 2), (0, 1))
Traceback (most recent call last):
...
ValueError: Sample data and Target data do not have matching lengths
"""
self.sample = sample
if len(self.sample) == 0:
raise ValueError("Sample data can not be empty")
self.target = target
if len(self.target) == 0:
raise ValueError("Target data can not be empty")
if len(self.sample) != len(self.target):
raise ValueError("Sample data and Target data do not have matching lengths")
self.learning_rate = learning_rate
self.epoch_number = epoch_number
self.bias = bias
self.number_sample = len(sample)
self.col_sample = len(sample[0]) # number of columns in dataset
self.weight = []
def training(self) -> None:
"""
Trains perceptron for epochs <= given number of epochs
:return: None
>>> data = [[2.0149, 0.6192, 10.9263]]
>>> targets = [-1]
>>> perceptron = Perceptron(data,targets)
>>> perceptron.training() # doctest: +ELLIPSIS
('\\nEpoch:\\n', ...)
...
"""
for sample in self.sample:
sample.insert(0, self.bias)
for i in range(self.col_sample):
self.weight.append(random.random())
self.weight.insert(0, self.bias)
epoch_count = 0
while True:
has_misclassified = False
for i in range(self.number_sample):
u = 0
for j in range(self.col_sample + 1):
u = u + self.weight[j] * self.sample[i][j]
y = self.sign(u)
if y != self.target[i]:
for j in range(self.col_sample + 1):
self.weight[j] = (
self.weight[j]
+ self.learning_rate
* (self.target[i] - y)
* self.sample[i][j]
)
has_misclassified = True
# print('Epoch: \n',epoch_count)
epoch_count = epoch_count + 1
# if you want control the epoch or just by error
if not has_misclassified:
print(("\nEpoch:\n", epoch_count))
print("------------------------\n")
# if epoch_count > self.epoch_number or not error:
break
def sort(self, sample) -> None:
"""
:param sample: example row to classify as P1 or P2
:return: None
>>> data = [[2.0149, 0.6192, 10.9263]]
>>> targets = [-1]
>>> perceptron = Perceptron(data,targets)
>>> perceptron.training() # doctest: +ELLIPSIS
('\\nEpoch:\\n', ...)
...
>>> perceptron.sort([-0.6508, 0.1097, 4.0009]) # doctest: +ELLIPSIS
('Sample: ', ...)
classification: P...
"""
if len(self.sample) == 0:
raise ValueError("Sample data can not be empty")
sample.insert(0, self.bias)
u = 0
for i in range(self.col_sample + 1):
u = u + self.weight[i] * sample[i]
y = self.sign(u)
if y == -1:
print(("Sample: ", sample))
print("classification: P1")
else:
print(("Sample: ", sample))
print("classification: P2")
def sign(self, u: float) -> int:
"""
threshold function for classification
:param u: input number
:return: 1 if the input is greater than 0, otherwise -1
>>> data = [[0],[-0.5],[0.5]]
>>> targets = [1,-1,1]
>>> perceptron = Perceptron(data,targets)
>>> perceptron.sign(0)
1
>>> perceptron.sign(-0.5)
-1
>>> perceptron.sign(0.5)
1
"""
return 1 if u >= 0 else -1
samples = [
[-0.6508, 0.1097, 4.0009],
[-1.4492, 0.8896, 4.4005],
[2.0850, 0.6876, 12.0710],
[0.2626, 1.1476, 7.7985],
[0.6418, 1.0234, 7.0427],
[0.2569, 0.6730, 8.3265],
[1.1155, 0.6043, 7.4446],
[0.0914, 0.3399, 7.0677],
[0.0121, 0.5256, 4.6316],
[-0.0429, 0.4660, 5.4323],
[0.4340, 0.6870, 8.2287],
[0.2735, 1.0287, 7.1934],
[0.4839, 0.4851, 7.4850],
[0.4089, -0.1267, 5.5019],
[1.4391, 0.1614, 8.5843],
[-0.9115, -0.1973, 2.1962],
[0.3654, 1.0475, 7.4858],
[0.2144, 0.7515, 7.1699],
[0.2013, 1.0014, 6.5489],
[0.6483, 0.2183, 5.8991],
[-0.1147, 0.2242, 7.2435],
[-0.7970, 0.8795, 3.8762],
[-1.0625, 0.6366, 2.4707],
[0.5307, 0.1285, 5.6883],
[-1.2200, 0.7777, 1.7252],
[0.3957, 0.1076, 5.6623],
[-0.1013, 0.5989, 7.1812],
[2.4482, 0.9455, 11.2095],
[2.0149, 0.6192, 10.9263],
[0.2012, 0.2611, 5.4631],
]
exit = [
-1,
-1,
-1,
1,
1,
-1,
1,
-1,
1,
1,
-1,
1,
-1,
-1,
-1,
-1,
1,
1,
1,
1,
-1,
1,
1,
1,
1,
-1,
-1,
1,
-1,
1,
]
if __name__ == "__main__":
import doctest
doctest.testmod()
network = Perceptron(
sample=samples, target=exit, learning_rate=0.01, epoch_number=1000, bias=-1
)
network.training()
print("Finished training perceptron")
print("Enter values to predict or q to exit")
while True:
sample = []
for i in range(len(samples[0])):
observation = input("value: ").strip()
if observation == "q":
break
observation = float(observation)
sample.insert(i, observation)
network.sort(sample)