markdown stringlengths 0 1.02M | code stringlengths 0 832k | output stringlengths 0 1.02M | license stringlengths 3 36 | path stringlengths 6 265 | repo_name stringlengths 6 127 |
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We have 134 emoji faces, including a few terminator robots. We'll again be using the [sklearn](https://scikit-learn.org/) library to create our model. The interface is usually the same, and for gaussian anomaly detection, sklearn again expect a NumPy matrix where the rows are our images and the columns are the pixels. ... | import numpy as np
arrays = [np.asarray(im) for im in images]
# 64 * 64 = 4096
vectors = [arr.reshape((4096,)) for arr in arrays]
data = np.stack(vectors) | _____no_output_____ | CC-BY-4.0 | data_analysis/3.3_anomaly_detection/anomaly_detection.ipynb | camille-vanhoffelen/modern-ML-engineer |
3. Training Next, we will create an [`EllipticEnvelope`](https://scikit-learn.org/stable/modules/generated/sklearn.covariance.EllipticEnvelope.html) object. This will fit a multi-variate gaussian distribution to our data. It then allows us to pick a threshold to define an _ellipsoid_ decision boundary , and detect out... | from sklearn.covariance import EllipticEnvelope
cov = EllipticEnvelope(random_state=0).fit(data) | _____no_output_____ | CC-BY-4.0 | data_analysis/3.3_anomaly_detection/anomaly_detection.ipynb | camille-vanhoffelen/modern-ML-engineer |
😰 What's happening? Why is it stuck? Have the killer robots already taken over? No need to panic, this kind of hiccup is very common when dealing with machine learning algorithms. We can kill the process (before it fries our laptop fan) by clicking the `stop` button ⬛️ in the notebook toolbar.Most learning algorithms ... | from sklearn.decomposition import PCA
pca = PCA(n_components=40)
pca.fit(data)
components = pca.transform(data)
components.shape | _____no_output_____ | CC-BY-4.0 | data_analysis/3.3_anomaly_detection/anomaly_detection.ipynb | camille-vanhoffelen/modern-ML-engineer |
💪 Visualise the eigenvector images of our PCA model. You can use the code from lecture 3.2!🧠 Can you explain what those eigenvector images represent? Why are they different than from the full emoji dataset?Fantastic, we've managed to reduce the number of dimensions by 99%! Hopefully that should be enough to make our ... | cov = EllipticEnvelope(random_state=0).fit(components) | _____no_output_____ | CC-BY-4.0 | data_analysis/3.3_anomaly_detection/anomaly_detection.ipynb | camille-vanhoffelen/modern-ML-engineer |
😅 that was fast! 4. PredictionWe can now use our fitted gaussian distribution to detect the outliers in our `data`. For this, we use the `.predict()` method: | y = cov.predict(components)
y | _____no_output_____ | CC-BY-4.0 | data_analysis/3.3_anomaly_detection/anomaly_detection.ipynb | camille-vanhoffelen/modern-ML-engineer |
`y` is our vector of predictions, where $1$ is a normal data point, and $-1$ is an anomaly. We can therefore iterate through our original `arrays` to find outliers: | outliers = []
for i in range(0, len(arrays)):
if y[i] == -1:
outliers.append(arrays[i])
len(outliers)
import matplotlib.pyplot as plt
fig, axs = plt.subplots(dpi=150, nrows=2, ncols=7)
for outlier, ax in zip(outliers, axs.flatten()):
ax.imshow(outlier, cmap='gray', vmin=0, vmax=255)
ax.get_xaxis()... | _____no_output_____ | CC-BY-4.0 | data_analysis/3.3_anomaly_detection/anomaly_detection.ipynb | camille-vanhoffelen/modern-ML-engineer |
THERE'S OUR TERMINATORS! 🤖 We can count 5 of them in total. Notice how some real emoji faces were also detected as outliers. This is perhaps a sign that we should change our _threshold_ , to make the ellipsoid decision boundary smaller. In fact, we didn't even specify a threshold before, we just used the default value... | cov = EllipticEnvelope(random_state=0, contamination=0.05).fit(components)
y = cov.predict(components)
outliers = []
for i in range(0, len(arrays)):
if y[i] == -1:
outliers.append(arrays[i])
fig, axs = plt.subplots(dpi=150, nrows=1, ncols=7)
for outlier, ax in zip(outliers, axs.flatten()):
ax... | _____no_output_____ | CC-BY-4.0 | data_analysis/3.3_anomaly_detection/anomaly_detection.ipynb | camille-vanhoffelen/modern-ML-engineer |
Better! `contamination=0.05` was a better choice of threshold, and we assessed this through _manual inspection_. This means we went through the results and used our human jugement to change the value of this _hyperparameter_.ℹ️ Notice how our outlier detection is not _perfect_. Some emojis were also erroneously detecte... | # Dimesionality reduction to 2
pca_model = PCA(n_components=2)
pca_model.fit(data) # fit the model
T = pca_model.transform(data) # transform the 'normalized model'
plt.scatter(T[:, 0], T[:, 1],
# use the predictions as color
c=y,
marker='o',
alpha=0.4
)
plt.titl... | _____no_output_____ | CC-BY-4.0 | data_analysis/3.3_anomaly_detection/anomaly_detection.ipynb | camille-vanhoffelen/modern-ML-engineer |
We can notice that most of the outliers are clearly _separable_ from the bulk of the dataset, even with only 2 principal components. One outlier is very much within the main cluster however. This could be explained by the dimensionality reduction, i.e that this point is separated from the cluster in other dimensions, o... | from matplotlib import offsetbox
def plot_components(data, model, images=None, ax=None,
thumb_frac=0.05, cmap='gray'):
ax = ax or plt.gca()
proj = model.fit_transform(data)
ax.plot(proj[:, 0], proj[:, 1], '.k')
if images is not None:
min_dist_2 = (thumb_frac * max(... | _____no_output_____ | CC-BY-4.0 | data_analysis/3.3_anomaly_detection/anomaly_detection.ipynb | camille-vanhoffelen/modern-ML-engineer |
Import Necessary Libraries | import numpy as np
import pandas as pd
from sklearn.model_selection import train_test_split
from sklearn import preprocessing
from sklearn.ensemble import RandomForestClassifier
from sklearn import svm
from sklearn.metrics import precision_score, recall_score
# display images
from IPython.display import Image
# linear... | _____no_output_____ | MIT | Titanic.ipynb | hashmat3525/Titanic |
Titanic Titanic was a British passenger liner that sank in the North Atlantic Ocean in the early morning hours of 15 April 1912, after it collided with an iceberg during its maiden voyage from Southampton to New York City. There were an estimated 2,224 passengers and crew aboard the ship, and more than 1,500 died, mak... | # Image of Titanic ship
Image(filename='C:/Users/Nemgeree Armanonah/Documents/GitHub/Titanic/images/ship.jpeg') | _____no_output_____ | MIT | Titanic.ipynb | hashmat3525/Titanic |
Getting the Data | #reading train.csv
data = pd.read_csv('./titanic datasets/train.csv')
data | _____no_output_____ | MIT | Titanic.ipynb | hashmat3525/Titanic |
Exploring Data | data.info() | <class 'pandas.core.frame.DataFrame'>
RangeIndex: 891 entries, 0 to 890
Data columns (total 12 columns):
PassengerId 891 non-null int64
Survived 891 non-null int64
Pclass 891 non-null int64
Name 891 non-null object
Sex 891 non-null object
Age 714 non-null float64
SibSp ... | MIT | Titanic.ipynb | hashmat3525/Titanic |
Describe Statistics Describe method is used to view some basic statistical details like PassengerId,Servived,Age etc. | data.describe() | _____no_output_____ | MIT | Titanic.ipynb | hashmat3525/Titanic |
View All Features | data.columns.values | _____no_output_____ | MIT | Titanic.ipynb | hashmat3525/Titanic |
What features could contribute to a high survival rate ? To Us it would make sense if everything except ‘PassengerId’, ‘Ticket’ and ‘Name’ would be correlated with a high survival rate. | # defining variables
survived = 'survived'
not_survived = 'not survived'
# data to be plotted
fig, axes = plt.subplots(nrows=1, ncols=2,figsize=(10, 4))
women = data[data['Sex']=='female']
men = data[data['Sex']=='male']
# plot the data
ax = sns.distplot(women[women['Survived']==1].Age.dropna(), bins=18, label = survi... | _____no_output_____ | MIT | Titanic.ipynb | hashmat3525/Titanic |
Data Processing |
def handle_non_numerical_data(df):
columns = df.columns.values
for column in columns:
text_digit_vals = {}
def convert_to_int(val):10
return text_digit_vals[val]
#print(column,df[column].dtype)
if df[column].dtype != np.int64 and df[column].dtype != np.float64... | _____no_output_____ | MIT | Titanic.ipynb | hashmat3525/Titanic |
Gaussian Transformation with Scikit-learnScikit-learn has recently released transformers to do Gaussian mappings as they call the variable transformations. The PowerTransformer allows to do Box-Cox and Yeo-Johnson transformation. With the FunctionTransformer, we can specify any function we want.The transformers per se... | import pandas as pd
import numpy as np
import matplotlib.pyplot as plt
import scipy.stats as stats
from sklearn.preprocessing import FunctionTransformer, PowerTransformer
# load the data
data = pd.read_csv('../houseprice.csv')
data.head() | _____no_output_____ | BSD-3-Clause | 07.02-Gaussian-transformation-sklearn.ipynb | sri-spirited/feature-engineering-for-ml |
Let's select the numerical and positive variables in the dataset for this demonstration. As most of the transformations require the variables to be positive. | cols = []
for col in data.columns:
if data[col].dtypes != 'O' and col != 'Id': # if the variable is numerical
if np.sum(np.where(data[col] <= 0, 1, 0)) == 0: # if the variable is positive
cols.append(col) # append variable to the list
cols
# let's explore the distribution... | _____no_output_____ | BSD-3-Clause | 07.02-Gaussian-transformation-sklearn.ipynb | sri-spirited/feature-engineering-for-ml |
Plots to assess normalityTo visualise the distribution of the variables, we plot a histogram and a Q-Q plot. In the Q-Q pLots, if the variable is normally distributed, the values of the variable should fall in a 45 degree line when plotted against the theoretical quantiles. We discussed this extensively in Section 3 o... | # plot the histograms to have a quick look at the variable distribution
# histogram and Q-Q plots
def diagnostic_plots(df, variable):
# function to plot a histogram and a Q-Q plot
# side by side, for a certain variable
plt.figure(figsize=(15,6))
plt.subplot(1, 2, 1)
df[variable].hist(bins... | _____no_output_____ | BSD-3-Clause | 07.02-Gaussian-transformation-sklearn.ipynb | sri-spirited/feature-engineering-for-ml |
Logarithmic transformation | # create a log transformer
transformer = FunctionTransformer(np.log, validate=True)
# transform all the numerical and positive variables
data_t = transformer.transform(data[cols].fillna(1))
# Scikit-learn returns NumPy arrays, so capture in dataframe
# note that Scikit-learn will return an array with
# only the colum... | _____no_output_____ | BSD-3-Clause | 07.02-Gaussian-transformation-sklearn.ipynb | sri-spirited/feature-engineering-for-ml |
Reciprocal transformation | # create the transformer
transformer = FunctionTransformer(lambda x: 1/x, validate=True)
# also
# transformer = FunctionTransformer(np.reciprocal, validate=True)
# transform the positive variables
data_t = transformer.transform(data[cols].fillna(1))
# re-capture in a dataframe
data_t = pd.DataFrame(data_t, columns =... | _____no_output_____ | BSD-3-Clause | 07.02-Gaussian-transformation-sklearn.ipynb | sri-spirited/feature-engineering-for-ml |
Square root transformation | transformer = FunctionTransformer(lambda x: x**(1/2), validate=True)
# also
# transformer = FunctionTransformer(np.sqrt, validate=True)
data_t = transformer.transform(data[cols].fillna(1))
data_t = pd.DataFrame(data_t, columns = cols)
diagnostic_plots(data_t, 'GrLivArea')
diagnostic_plots(data_t, 'MSSubClass') | _____no_output_____ | BSD-3-Clause | 07.02-Gaussian-transformation-sklearn.ipynb | sri-spirited/feature-engineering-for-ml |
Exponential | transformer = FunctionTransformer(lambda x: x**(1/1.2), validate=True)
data_t = transformer.transform(data[cols].fillna(1))
data_t = pd.DataFrame(data_t, columns = cols)
diagnostic_plots(data_t, 'GrLivArea')
diagnostic_plots(data_t, 'MSSubClass') | _____no_output_____ | BSD-3-Clause | 07.02-Gaussian-transformation-sklearn.ipynb | sri-spirited/feature-engineering-for-ml |
Box-Cox transformation | # create the transformer
transformer = PowerTransformer(method='box-cox', standardize=False)
# find the optimal lambda using the train set
transformer.fit(data[cols].fillna(1))
# transform the data
data_t = transformer.transform(data[cols].fillna(1))
# capture data in a dataframe
data_t = pd.DataFrame(data_t, column... | _____no_output_____ | BSD-3-Clause | 07.02-Gaussian-transformation-sklearn.ipynb | sri-spirited/feature-engineering-for-ml |
Yeo-JohnsonYeo-Johnson is an adaptation of Box-Cox that can also be used in negative value variables. So let's expand the list of variables for the demo, to include those that contain zero and negative values as well. | cols = [
'MSSubClass', 'LotFrontage', 'LotArea', 'OverallQual',
'OverallCond', 'MasVnrArea', 'BsmtFinSF1',
'BsmtFinSF2', 'BsmtUnfSF', 'TotalBsmtSF', '1stFlrSF', '2ndFlrSF',
'LowQualFinSF', 'GrLivArea', 'BsmtFullBath', 'BsmtHalfBath', 'FullBath',
'HalfBath', 'BedroomAbvGr', 'KitchenAbvGr', 'TotRmsAbv... | _____no_output_____ | BSD-3-Clause | 07.02-Gaussian-transformation-sklearn.ipynb | sri-spirited/feature-engineering-for-ml |
Money Channel | with open('../data/moneychanel.json') as json_data:
data = json.load(json_data)
len(data)
data[13]
entry = []
for i, row in tqdm_notebook(enumerate(data)):
if len(row['Stock Include']) > 1: continue
for stock in row['Stock Include']:
if stock in target_stocks:
entry.append([
... | _____no_output_____ | Apache-2.0 | EDA/news_stat.ipynb | pcrete/stock_prediction_using_contextual_information |
Pantip | with open('../data/pantip.json') as json_data:
data = json.load(json_data)
len(data)
data[3]
data[3]['date']
data[3]['stock']
text = data[3]['head']+' '+data[3]['content']
text
for x in data[3]['comments']:
text += x['message']
text
entry = []
for i, row in tqdm_notebook(enumerate(data)):
if len(row['stock... | _____no_output_____ | Apache-2.0 | EDA/news_stat.ipynb | pcrete/stock_prediction_using_contextual_information |
Twitter | with open('../data/twitter.json') as json_data:
data = json.load(json_data)
len(data)
data[0]
entry = []
for i, row in tqdm_notebook(enumerate(data)):
if len(row['Stock Include']) > 1: continue
for stock in row['Stock Include']:
if stock in target_stocks:
entry.append([
r... | _____no_output_____ | Apache-2.0 | EDA/news_stat.ipynb | pcrete/stock_prediction_using_contextual_information |
In-Class Coding Lab: IterationsThe goals of this lab are to help you to understand:- How loops work.- The difference between definite and indefinite loops, and when to use each.- How to build an indefinite loop with complex exit conditions.- How to create a program from a complex idea. Understanding IterationsIterati... | i = 1
while i <= 3:
print(i,"Mississippi...")
i=i+1
print("Blitz!") | 1 Mississippi...
2 Mississippi...
3 Mississippi...
Blitz!
| MIT | content/lessons/05/Class-Coding-Lab/CCL-Iterations.ipynb | MahopacHS/spring2019-rizzenM |
Breaking it down...The `while` statement on line 2 starts the loop. The code indented beneath it (lines 3-4) will repeat, in a linear fashion until the Boolean expression on line 2 `i <= 3` is `False`, at which time the program continues with line 5. Some TerminologyWe call `i <=3` the loop's **exit condition**. The v... | ## WARNING!!! INFINITE LOOP AHEAD
## IF YOU RUN THIS CODE YOU WILL NEED TO KILL YOUR BROWSER AND SHUT DOWN JUPYTER NOTEBOOK
i = 1
while i <= 3:
print(i,"Mississippi...")
# i=i+1
print("Blitz!") | _____no_output_____ | MIT | content/lessons/05/Class-Coding-Lab/CCL-Iterations.ipynb | MahopacHS/spring2019-rizzenM |
For loopsTo prevent an infinite loop when the loop is definite, we use the `for` statement. Here's the same program using `for`: | for i in range(1,4):
print(i,"Mississippi...")
print("Blitz!") | 1 Mississippi...
2 Mississippi...
3 Mississippi...
Blitz!
| MIT | content/lessons/05/Class-Coding-Lab/CCL-Iterations.ipynb | MahopacHS/spring2019-rizzenM |
One confusing aspect of this loop is `range(1,4)` why does this loop from 1 to 3? Why not 1 to 4? Well it has to do with the fact that computers start counting at zero. The easier way to understand it is if you subtract the two numbers you get the number of times it will loop. So for example, 4-1 == 3. Now Try ItIn the... | # TODO Write code here
| 10 Mississippi...
11 Mississippi...
12 Mississippi...
13 Mississippi...
14 Mississippi...
15 Mississippi...
Blitz!
| MIT | content/lessons/05/Class-Coding-Lab/CCL-Iterations.ipynb | MahopacHS/spring2019-rizzenM |
Indefinite loopsWith **indefinite loops** we do not know how many times the program will execute. This is typically based on user action, and therefore our loop is subject to the whims of whoever interacts with it. Most applications like spreadsheets, photo editors, and games use indefinite loops. They'll run on your ... | name = ""
while name != 'mike':
name = input("Say my name! : ")
print("Nope, my name is not %s! " %(name)) | Say my name! : rizzen
Nope, my name is not rizzen!
Say my name! : mike
Nope, my name is not mike!
| MIT | content/lessons/05/Class-Coding-Lab/CCL-Iterations.ipynb | MahopacHS/spring2019-rizzenM |
The classic problem with indefinite loops is that its really difficult to get the application's logic to line up with the exit condition. For example we need to set `name = ""` in line 1 so that line 2 start out as `True`. Also we have this wonky logic where when we say `'mike'` it still prints `Nope, my name is not mi... | while True:
name = input("Say my name!: ")
if name == 'mike':
break
print("Nope, my name is not %s!" %(name)) | Say my name!: bill
Nope, my name is not bill!
Say my name!: dave
Nope, my name is not dave!
Say my name!: mike
| MIT | content/lessons/05/Class-Coding-Lab/CCL-Iterations.ipynb | MahopacHS/spring2019-rizzenM |
Multiple exit conditionsThis indefinite loop pattern makes it easy to add additional exit conditions. For example, here's the program again, but it now stops when you say my name or type in 3 wrong names. Make sure to run this program a couple of times. First enter mike to exit the program, next enter the wrong name 3... | times = 0
while True:
name = input("Say my name!: ")
times = times + 1
if name == 'mike':
print("You got it!")
break
if times == 3:
print("Game over. Too many tries!")
break
print("Nope, my name is not %s!" %(name)) | Say my name!: mike
You got it!
| MIT | content/lessons/05/Class-Coding-Lab/CCL-Iterations.ipynb | MahopacHS/spring2019-rizzenM |
Number sumsLet's conclude the lab with you writing your own program whichuses an indefinite loop. We'll provide the to-do list, you write the code. This program should ask for floating point numbers as input and stops looping when **the total of the numbers entered is over 100**, or **more than 5 numbers have been ent... | ## TO-DO List
#1 count = 0
#2 total = 0
#3 loop Indefinitely
#4. input a number
#5 increment count
#6 add number to total
#7 if count equals 5 stop looping
#8 if total greater than 100 stop looping
#9 print total and count
# Write Code here:
count = 0
total = 0
while true:
number = ... | _____no_output_____ | MIT | content/lessons/05/Class-Coding-Lab/CCL-Iterations.ipynb | MahopacHS/spring2019-rizzenM |
data_processing.numeric> Numeric related data processing- toc: True | #export
import pandas as pd
# export
def moving_average(data_frame: pd.DataFrame = None,
window: int=7,
group_col: str = None,
value_col: str = None,
shift=0)->pd.DataFrame:
df = data_frame.copy()
ma_col = '{... | _____no_output_____ | Apache-2.0 | notebooks/data_processing_numeric.ipynb | hirogen317/chamomile |
第8章: ニューラルネット第6章で取り組んだニュース記事のカテゴリ分類を題材として，ニューラルネットワークでカテゴリ分類モデルを実装する．なお，この章ではPyTorch, TensorFlow, Chainerなどの機械学習プラットフォームを活用せよ． 70. 単語ベクトルの和による特徴量***問題50で構築した学習データ，検証データ，評価データを行列・ベクトルに変換したい．例えば，学習データについて，すべての事例$x_i$の特徴ベクトル$\boldsymbol{x}_i$を並べた行列$X$と正解ラベルを並べた行列（ベクトル）$Y$を作成したい．$$X = \begin{pmatrix} \boldsymbol{x}_1 \... | !wget https://archive.ics.uci.edu/ml/machine-learning-databases/00359/NewsAggregatorDataset.zip
!unzip NewsAggregatorDataset.zip
!wc -l ./newsCorpora.csv
!head -10 ./newsCorpora.csv
# 読込時のエラー回避のためダブルクォーテーションをシングルクォーテーションに置換
!sed -e 's/"/'\''/g' ./newsCorpora.csv > ./newsCorpora_re.csv
import pandas as pd
from sklearn.m... | _____no_output_____ | MIT | chapter08.ipynb | fKVzGecnXYhM/nlp100 |
71. 単層ニューラルネットワークによる予測***問題70で保存した行列を読み込み，学習データについて以下の計算を実行せよ．$$\hat{y}_1=softmax(x_1W),\\\hat{Y}=softmax(X_{[1:4]}W)$$ただし，$softmax$はソフトマックス関数，$X_{[1:4]}∈\mathbb{R}^{4×d}$は特徴ベクトル$x_1$,$x_2$,$x_3$,$x_4$を縦に並べた行列である．$$X_{[1:4]}=\begin{pmatrix}x_1\\x_2\\x_3\\x_4\end{pmatrix}$$行列$W \in \mathbb{R}^{d \times L}$は単層ニューラルネットワー... | from torch import nn
torch.manual_seed(0)
class SLPNet(nn.Module):
def __init__(self, input_size, output_size):
super().__init__()
self.fc = nn.Linear(input_size, output_size, bias=False) # Linear(入力次元数, 出力次元数)
nn.init.normal_(self.fc.weight, 0.0, 1.0) # 正規乱数で重みを初期化
def forward(self, x):
x = sel... | tensor([[0.4273, 0.0958, 0.2492, 0.2277],
[0.2445, 0.2431, 0.0197, 0.4927],
[0.7853, 0.1132, 0.0291, 0.0724],
[0.5279, 0.2319, 0.0873, 0.1529]], grad_fn=<SoftmaxBackward>)
| MIT | chapter08.ipynb | fKVzGecnXYhM/nlp100 |
72. 損失と勾配の計算***学習データの事例$x_1$と事例集合$x_1$,$x_2$,$x_3$,$x_4$に対して，クロスエントロピー損失と，行列$W$に対する勾配を計算せよ．なお，ある事例$x_i$に対して損失は次式で計算される．$$l_i=−log[事例x_iがy_iに分類される確率]$$ただし，事例集合に対するクロスエントロピー損失は，その集合に含まれる各事例の損失の平均とする． | criterion = nn.CrossEntropyLoss()
l_1 = criterion(model.forward(X_train[:1]), y_train[:1]) # 入力ベクトルはsoftmax前の値
model.zero_grad() # 勾配をゼロで初期化
l_1.backward() # 勾配を計算
print(f'損失: {l_1:.4f}')
print(f'勾配:\n{model.fc.weight.grad}')
l = criterion(model.forward(X_train[:4]), y_train[:4])
model.zero_grad()
l.backward()
print... | 損失: 1.8321
勾配:
tensor([[-0.0063, 0.0042, -0.0139, ..., -0.0272, 0.0201, 0.0263],
[-0.0047, -0.0025, 0.0195, ..., 0.0196, 0.0160, 0.0009],
[ 0.0184, -0.0110, -0.0148, ..., 0.0070, -0.0055, -0.0001],
[-0.0074, 0.0092, 0.0092, ..., 0.0006, -0.0306, -0.0272]])
| MIT | chapter08.ipynb | fKVzGecnXYhM/nlp100 |
73. 確率的勾配降下法による学習***確率的勾配降下法（SGD: Stochastic Gradient Descent）を用いて，行列$W$を学習せよ．なお，学習は適当な基準で終了させればよい（例えば「100エポックで終了」など）． | from torch.utils.data import Dataset
class CreateDataset(Dataset):
def __init__(self, X, y): # datasetの構成要素を指定
self.X = X
self.y = y
def __len__(self): # len(dataset)で返す値を指定
return len(self.y)
def __getitem__(self, idx): # dataset[idx]で返す値を指定
if isinstance(idx, torch.Tensor):
idx = idx... | epoch: 1, loss_train: 0.4686, loss_valid: 0.3738
epoch: 2, loss_train: 0.3159, loss_valid: 0.3349
epoch: 3, loss_train: 0.2846, loss_valid: 0.3248
epoch: 4, loss_train: 0.2689, loss_valid: 0.3194
epoch: 5, loss_train: 0.2580, loss_valid: 0.3094
epoch: 6, loss_train: 0.2503, loss_valid: 0.3089
epoch: 7, loss_train: 0.24... | MIT | chapter08.ipynb | fKVzGecnXYhM/nlp100 |
74. 正解率の計測***問題73で求めた行列を用いて学習データおよび評価データの事例を分類したとき，その正解率をそれぞれ求めよ． | def calculate_accuracy(model, X, y):
model.eval()
with torch.no_grad():
outputs = model(X)
pred = torch.argmax(outputs, dim=-1)
return (pred == y).sum().item() / len(y)
# 正解率の確認
acc_train = calculate_accuracy(model, X_train, y_train)
acc_test = calculate_accuracy(model, X_test, y_test)
print(f'正解率（学習データ）... | 正解率（学習データ）：0.925
正解率（評価データ）：0.902
| MIT | chapter08.ipynb | fKVzGecnXYhM/nlp100 |
75. 損失と正解率のプロット***問題73のコードを改変し，各エポックのパラメータ更新が完了するたびに，訓練データでの損失，正解率，検証データでの損失，正解率をグラフにプロットし，学習の進捗状況を確認できるようにせよ． | def calculate_loss_and_accuracy(model, criterion, loader):
model.eval()
loss = 0.0
total = 0
correct = 0
with torch.no_grad():
for inputs, labels in loader:
outputs = model(inputs)
loss += criterion(outputs, labels).item()
pred = torch.argmax(outputs, dim=-1)
total += len(inputs)
... | _____no_output_____ | MIT | chapter08.ipynb | fKVzGecnXYhM/nlp100 |
76. チェックポイント***問題75のコードを改変し，各エポックのパラメータ更新が完了するたびに，チェックポイント（学習途中のパラメータ（重み行列など）の値や最適化アルゴリズムの内部状態）をファイルに書き出せ． | # モデルの定義
model = SLPNet(300, 4)
# 損失関数の定義
criterion = nn.CrossEntropyLoss()
# オプティマイザの定義
optimizer = torch.optim.SGD(model.parameters(), lr=1e-1)
# 学習
num_epochs = 10
log_train = []
log_valid = []
for epoch in range(num_epochs):
# 訓練モードに設定
model.train()
for inputs, labels in dataloader_train:
# 勾配をゼロで初期化
... | epoch: 1, loss_train: 0.3281, accuracy_train: 0.8886, loss_valid: 0.3622, accuracy_valid: 0.8698
epoch: 2, loss_train: 0.2928, accuracy_train: 0.9040, loss_valid: 0.3351, accuracy_valid: 0.8832
epoch: 3, loss_train: 0.2638, accuracy_train: 0.9125, loss_valid: 0.3138, accuracy_valid: 0.8870
epoch: 4, loss_train: 0.2571,... | MIT | chapter08.ipynb | fKVzGecnXYhM/nlp100 |
77. ミニバッチ化***問題76のコードを改変し，$B$事例ごとに損失・勾配を計算し，行列$W$の値を更新せよ（ミニバッチ化）．$B$の値を$1,2,4,8,…$と変化させながら，1エポックの学習に要する時間を比較せよ． | import time
def train_model(dataset_train, dataset_valid, batch_size, model, criterion, optimizer, num_epochs):
# dataloaderの作成
dataloader_train = DataLoader(dataset_train, batch_size=batch_size, shuffle=True)
dataloader_valid = DataLoader(dataset_valid, batch_size=len(dataset_valid), shuffle=False)
# 学習
lo... | バッチサイズ: 1
epoch: 1, loss_train: 0.3310, accuracy_train: 0.8858, loss_valid: 0.3579, accuracy_valid: 0.8795, 4.1217sec
バッチサイズ: 2
epoch: 1, loss_train: 0.2985, accuracy_train: 0.8967, loss_valid: 0.3289, accuracy_valid: 0.8907, 2.3251sec
バッチサイズ: 4
epoch: 1, loss_train: 0.2895, accuracy_train: 0.9000, loss_valid: 0.3226, ... | MIT | chapter08.ipynb | fKVzGecnXYhM/nlp100 |
78. GPU上での学習***問題77のコードを改変し，GPU上で学習を実行せよ． | def calculate_loss_and_accuracy(model, criterion, loader, device):
model.eval()
loss = 0.0
total = 0
correct = 0
with torch.no_grad():
for inputs, labels in loader:
inputs = inputs.to(device)
labels = labels.to(device)
outputs = model(inputs)
loss += criterion(outputs, labels).item... | バッチサイズ: 1
epoch: 1, loss_train: 0.3322, accuracy_train: 0.8842, loss_valid: 0.3676, accuracy_valid: 0.8780, 10.2910sec
バッチサイズ: 2
epoch: 1, loss_train: 0.3038, accuracy_train: 0.8983, loss_valid: 0.3469, accuracy_valid: 0.8840, 5.0635sec
バッチサイズ: 4
epoch: 1, loss_train: 0.2929, accuracy_train: 0.9013, loss_valid: 0.3390,... | MIT | chapter08.ipynb | fKVzGecnXYhM/nlp100 |
79. 多層ニューラルネットワーク***問題78のコードを改変し，バイアス項の導入や多層化など，ニューラルネットワークの形状を変更しながら，高性能なカテゴリ分類器を構築せよ． | from torch.nn import functional as F
class MLPNet(nn.Module):
def __init__(self, input_size, mid_size, output_size, mid_layers):
super().__init__()
self.mid_layers = mid_layers
self.fc = nn.Linear(input_size, mid_size)
self.fc_mid = nn.Linear(mid_size, mid_size)
self.fc_out = nn.Linear(mid_size, ... | 正解率（学習データ）：0.960
正解率（評価データ）：0.913
| MIT | chapter08.ipynb | fKVzGecnXYhM/nlp100 |
Analyse a series Under construction | import os
import pandas as pd
from IPython.display import Image as DImage
from IPython.core.display import display, HTML
import series_details
# Plotly helps us make pretty charts
import plotly.offline as py
import plotly.graph_objs as go
# Make sure data directory exists
os.makedirs('../../data/RecordSearch/images',... | _____no_output_____ | MIT | recordsearch/2-Analyse-a-series.ipynb | GLAM-Workbench/glam-workbench-presentations |
This notebook is for analysing a series that you've already harvested. If you haven't harvested any data yet, then you need to go back to the ['Harvesting a series' notebook](Harvesting series.ipynb). | # What series do you want to analyse?
# Insert the series id between the quotes.
series = 'J2483'
# Load the CSV data for the specified series into a dataframe. Parse the dates as dates!
df = pd.read_csv('../data/RecordSearch/{}.csv'.format(series.replace('/', '-')), parse_dates=['start_date', 'end_date']) | _____no_output_____ | MIT | recordsearch/2-Analyse-a-series.ipynb | GLAM-Workbench/glam-workbench-presentations |
Remember that you can download harvested data from the workbench [data directory](../data/RecordSearch). Get some summary dataWe're going to create a simple summary of some of the main characteristics of the series, as reflected in the harvested files. | # We're going to assemble some summary data about the series in a 'summary' dictionary
# Let's create the dictionary and add the series identifier
summary = {'series': series}
# The 'shape' property returns the number of rows and columns. So 'shape[0]' gives us the number of items harvested.
summary['total_items'] = df... | _____no_output_____ | MIT | recordsearch/2-Analyse-a-series.ipynb | GLAM-Workbench/glam-workbench-presentations |
Note that a slightly enhanced version of the code above is available in the `series_details` module that you can import into any notebook. So to create a summary of a series you can just: | # Import the module
import series_details
# Call display_series() providing the series name and the dataframe
series_details.display_summary(series, df) | _____no_output_____ | MIT | recordsearch/2-Analyse-a-series.ipynb | GLAM-Workbench/glam-workbench-presentations |
Plot the contents datesPlotting the dates is a bit tricky. Each file can have both a start date and an end date. So if we want to plot the years covered by a file, we need to include all the years between the start and end dates. Also dates can be recorded at different levels of granularity, for specific days to just ... | # Fill any blank end dates with start dates
df['end_date'] = df[['end_date']].apply(lambda x: x.fillna(value=df['start_date']))
# This is a bit tricky.
# For each item we want to find the years that it has content from -- ie start_year <= year <= end_year.
# Then we want to put all the years from all the items togethe... | _____no_output_____ | MIT | recordsearch/2-Analyse-a-series.ipynb | GLAM-Workbench/glam-workbench-presentations |
Note that a slightly enhanced version of the code above is available in the series_details module that you can import into any notebook. So to create a summary of a series you can just: | # Import the module
import series_details
# Call plot_series() providing the series name and the dataframe
fig = series_details.plot_dates(df)
py.iplot(fig) | _____no_output_____ | MIT | recordsearch/2-Analyse-a-series.ipynb | GLAM-Workbench/glam-workbench-presentations |
Filter by words in file titles | # Find titles containing a particular phrase -- in this case 'wife'
# This creates a new dataframe
# Try changing this to filter for other words
search_term = 'wife'
df_filtered = df.loc[df['title'].str.contains(search_term, case=False)].copy()
df_filtered
# We can plot this filtered dataframe just like the series
fig... | _____no_output_____ | MIT | recordsearch/2-Analyse-a-series.ipynb | GLAM-Workbench/glam-workbench-presentations |
Filter by date range | start_year = '1920'
end_year = '1930'
df_filtered = df[(df['start_date'] >= start_year) & (df['end_date'] <= end_year)]
df_filtered | _____no_output_____ | MIT | recordsearch/2-Analyse-a-series.ipynb | GLAM-Workbench/glam-workbench-presentations |
N-gram frequencies in file titles | # Import TextBlob for text analysis
from textblob import TextBlob
import nltk
stopwords = nltk.corpus.stopwords.words('english')
# Combine all of the file titles into a single string
title_text = a = df['title'].str.lower().str.cat(sep=' ')
blob = TextBlob(title_text)
words = [[word, count] for word, count in blob.lowe... | _____no_output_____ | MIT | recordsearch/2-Analyse-a-series.ipynb | GLAM-Workbench/glam-workbench-presentations |
Pyopenssl[官方文档](https://www.pyopenssl.org/) 使用openssl生成私钥和公钥[参考资料](https://blog.csdn.net/huanhuanq1209/article/details/80899017)> openssl > genrsa -out private.pem 1024 > rsa -in public.pem -pubout -out rsa_public_key.pem 签名实例 | import OpenSSL
from OpenSSL._util import lib as _lib
FILETYPE_PEM = _lib.SSL_FILETYPE_PEM
import base64
def makeSign(message):
order = sorted(message)
sign_str = ""
for key in order:
sign_str = sign_str + "&{0}={1}".format(key,message[key])
sign_str = sign_str[1:]
print(... | 待签名的串 == 》 method=any&mobile=18300010001&name=Baird&sex=male
签名结果 ==》 b'\x84\xb9\xae\xc3{\xfb"\xb5\x9fA\x02\x9bZ\x16g\xd5\x90`\x1e\xc6\x87\xef\xb1\xef\xb3\x8a\xb7\xbc\xc3\x0e\xab45T\xfaK\x02\xc25\x82\xbag\xb9\x94\t\x8c\xc8\x0f\xe9\x81\xd7U\x80\xd6\xf9\x871q>V\xdfn\x0b\x8e\xac\x8a\xab#B\xab\xf3\xc6\xfaM\xc4\x95$\xa7\xef... | Apache-2.0 | python/modules/jupyter/Pyopenssl.ipynb | HHW-zhou/snippets |
验签实例 | def makeVerify(sign, sign_str):
sign = base64.b64decode(sign)
with open("public.pem","rb") as f:
pubkey = OpenSSL.crypto.load_publickey(FILETYPE_PEM, buffer=f.read())
x509 = OpenSSL.crypto.X509()
x509.set_pubkey(pubkey)
#验证通过返回None,否则抛出错误
try:
OpenSSL.crypto.verify(... | _____no_output_____ | Apache-2.0 | python/modules/jupyter/Pyopenssl.ipynb | HHW-zhou/snippets |
VacationPy---- Note* Keep an eye on your API usage. Use https://developers.google.com/maps/reporting/gmp-reporting as reference for how to monitor your usage and billing.* Instructions have been included for each segment. You do not have to follow them exactly, but they are included to help you think through the steps... | # Dependencies and Setup
import matplotlib.pyplot as plt
import pandas as pd
import numpy as np
import requests
import gmaps
import os
# Import API key
from api_keys import g_key | _____no_output_____ | ADSL | starter_code/.ipynb_checkpoints/VacationPy-checkpoint.ipynb | jackaloppy/python-api-challenge |
Store Part I results into DataFrame* Load the csv exported in Part I to a DataFrame | cities_df = pd.read_csv('../output_data/cities.csv')
cities_df.dropna(inplace = True)
cities_df.head() | _____no_output_____ | ADSL | starter_code/.ipynb_checkpoints/VacationPy-checkpoint.ipynb | jackaloppy/python-api-challenge |
Humidity Heatmap* Configure gmaps.* Use the Lat and Lng as locations and Humidity as the weight.* Add Heatmap layer to map. | gmaps.configure(api_key=g_key)
locations = cities_df[["Lat", "Lng"]]
humidity = cities_df["Humidity"]
fig = gmaps.figure()
heat_layer = gmaps.heatmap_layer(locations, weights=humidity,
dissipating=False, max_intensity=150,
point_radius=3)
fig.add_layer(... | _____no_output_____ | ADSL | starter_code/.ipynb_checkpoints/VacationPy-checkpoint.ipynb | jackaloppy/python-api-challenge |
Create new DataFrame fitting weather criteria* Narrow down the cities to fit weather conditions.* Drop any rows will null values. | ideal_df = cities_df[cities_df["Max Temp"].lt(80) &
cities_df["Max Temp"].gt(70) &
cities_df["Wind Speed"].lt(10) &
cities_df["Cloudiness"].eq(0) &
cities_df["Humidity"].lt(80) &
cities_df["Humidity"].gt(30)]
ideal_df | _____no_output_____ | ADSL | starter_code/.ipynb_checkpoints/VacationPy-checkpoint.ipynb | jackaloppy/python-api-challenge |
Hotel Map* Store into variable named `hotel_df`.* Add a "Hotel Name" column to the DataFrame.* Set parameters to search for hotels with 5000 meters.* Hit the Google Places API for each city's coordinates.* Store the first Hotel result into the DataFrame.* Plot markers on top of the heatmap. | hotel_df = ideal_df[["City", "Lat", "Lng", "Country"]].reset_index(drop=True)
hotel_df["Hotel Name"] = ""
params = {
"radius": 5000,
"types": "lodging",
"keyword": "hotel",
"key": g_key
}
for index, row in hotel_df.iterrows():
lat = row["Lat"]
lng = row["Lng"]
params["location"] = f"{lat},{l... | _____no_output_____ | ADSL | starter_code/.ipynb_checkpoints/VacationPy-checkpoint.ipynb | jackaloppy/python-api-challenge |
SLU07 - Regression with Linear Regression: Example notebook 1 - Writing linear modelsIn this section you have a few examples on how to implement simple and multiple linear models.Let's start by implementing the following:$$y = 1.25 + 5x$$ | def first_linear_model(x):
"""
Implements y = 1.25 + 5*x
Args:
x : float - input of model
Returns:
y : float - output of linear model
"""
y = 1.25 + 5 * x
return y
first_linear_model(1) | _____no_output_____ | MIT | S01 - Bootcamp and Binary Classification/SLU07 - Regression with Linear Regression/Example notebook.ipynb | claury/sidecar-academy-batch2 |
You should be thinking that this is too easy. So let's generalize it a bit. We'll write the code for the next equation:$$ y = a + bx $$ | def second_linear_model(x, a, b):
"""
Implements y = a + b * x
Args:
x : float - input of model
a : float - intercept of model
b : float - coefficient of model
Returns:
y : float - output of linear model
"""
y = a + b * x
return y
second_linear_model(1, 1... | _____no_output_____ | MIT | S01 - Bootcamp and Binary Classification/SLU07 - Regression with Linear Regression/Example notebook.ipynb | claury/sidecar-academy-batch2 |
Still very simple, right? Now what if we want to have a linear model with multiple variables, such as this one:$$ y = a + bx_1 + cx_2 + dx_3 $$You can follow the same logic and just write the following: | def first_multiple_linear_model(x_1, x_2, x_3, a, b, c, d):
"""
Implements y = a + b * x_1 + c * x_2 + d * x_3
Args:
x_1 : float - first input of model
x_2 : float - second input of model
x_3 : float - third input of model
a : float - intercept of model
b : flo... | _____no_output_____ | MIT | S01 - Bootcamp and Binary Classification/SLU07 - Regression with Linear Regression/Example notebook.ipynb | claury/sidecar-academy-batch2 |
However, you should already be seeing the problem. The bigger our model gets, the more variables we need to consider, so this is clearly not efficient. Now let's write the generic form for a linear model:$$ y = w_0 + \sum_{i=1}^{N} w_i x_i$$And we will implement the inputs and outputs of the model as vectors: | def second_multiple_linear_model(x, w):
"""
Implements y = w_0 + sum(x_i*w_i) (where i=1...N)
Args:
x : vector of input features with size N-1
w : vector of model weights with size N
Returns:
y : float - output of linear model
"""
w_0 = w[0]
y = w_0
... | _____no_output_____ | MIT | S01 - Bootcamp and Binary Classification/SLU07 - Regression with Linear Regression/Example notebook.ipynb | claury/sidecar-academy-batch2 |
You could go even one step further and use numpy to vectorize these computations. You can represent both vectors as numpy arrays and just do the same calculation: | import numpy as np
def vectorized_multiple_linear_model(x, w):
"""
Implements y = w_0 + sum(x_i*w_i) (where i=1...N)
Args:
x : numpy array with shape (N-1, ) of inputs
w : numpy array with shape (N, ) of model weights
Returns:
y : float - output of linear model
"""
... | _____no_output_____ | MIT | S01 - Bootcamp and Binary Classification/SLU07 - Regression with Linear Regression/Example notebook.ipynb | claury/sidecar-academy-batch2 |
Read more about numpy array and its manipulation at the end of this example notebook. This will be necessary as you will be requested to implement these types of models in a way that they can compute several samples with many features at once. 2 - Using sklearn's LinearRegressionThe following cells show you how to us... | import numpy as np
import matplotlib.pyplot as plt
np.random.seed(42)
X = np.arange(-10, 10) + np.random.rand(20)
y = 1.12 + .75 * X + 2. * np.random.rand(20)
plt.xlim((-10, 10))
plt.ylim((-20, 20))
plt.plot(X, y, 'b.') | _____no_output_____ | MIT | S01 - Bootcamp and Binary Classification/SLU07 - Regression with Linear Regression/Example notebook.ipynb | claury/sidecar-academy-batch2 |
2.1 Training the modelWe will now use the base data created and show you how to fit the scikitlearn LinearRegression model with the data: | from sklearn.linear_model import LinearRegression
# Since our numpy array has only 1 dimension, we need reshape
# it to become a column vector - which corresponds to 1 feature
# and N samples
X = X.reshape(-1, 1)
lr = LinearRegression()
lr.fit(X, y) | _____no_output_____ | MIT | S01 - Bootcamp and Binary Classification/SLU07 - Regression with Linear Regression/Example notebook.ipynb | claury/sidecar-academy-batch2 |
2.2 Coefficients and InterceptYou can get both the coefficients and the intercept from this model: | print('Coefficients: {}'.format(lr.coef_))
print('Intercept: {}'.format(lr.intercept_)) | Coefficients: [0.76238153]
Intercept: 2.030181639054948
| MIT | S01 - Bootcamp and Binary Classification/SLU07 - Regression with Linear Regression/Example notebook.ipynb | claury/sidecar-academy-batch2 |
2.3 Making predictionsWe can then make prediction with our model and see how they compare with the actual samples: | y_pred = lr.predict(X)
plt.xlim((-10, 10))
plt.ylim((-20, 20))
plt.plot(X, y, 'b.')
plt.plot(X, y_pred, 'r-') | _____no_output_____ | MIT | S01 - Bootcamp and Binary Classification/SLU07 - Regression with Linear Regression/Example notebook.ipynb | claury/sidecar-academy-batch2 |
2.4 Evaluating the modelWe can also extract the $R^2$ score of this model: | print('R² score: %f' % lr.score(X, y)) | R² score: 0.983519
| MIT | S01 - Bootcamp and Binary Classification/SLU07 - Regression with Linear Regression/Example notebook.ipynb | claury/sidecar-academy-batch2 |
Bonus examples: Numpy utilities With linear models, we normally have data that can be represented by either vectors or matrices. Even though you don't need advanced algebra knowledge to implement and understand the models presented, it is useful to understand its basics, since most of the computational part is typica... | import numpy as np
import pandas as pd | _____no_output_____ | MIT | S01 - Bootcamp and Binary Classification/SLU07 - Regression with Linear Regression/Example notebook.ipynb | claury/sidecar-academy-batch2 |
a) Pandas to numpy and backPandas stores our data in dataframes and series, which are very useful for visualization and even for some specific data operations we want to perform. However, for many algorithms that involve combination of numeric data, the standard form of implementing is by using numpy. Start by seeing ... | df = pd.read_csv('data/polynomial.csv')
df.head() | _____no_output_____ | MIT | S01 - Bootcamp and Binary Classification/SLU07 - Regression with Linear Regression/Example notebook.ipynb | claury/sidecar-academy-batch2 |
a.1) Pandas to numpyLet's transform our first column into a numpy vector. There are two ways of doing this, either by using the `.values` attribute: | np_array = df['x'].values
print(np_array[:10]) | [-0.97468167 1.04349486 1.67141609 -0.05145155 1.98901715 1.69483221
2.3605217 3.69166478 1.80589394 1.55395614]
| MIT | S01 - Bootcamp and Binary Classification/SLU07 - Regression with Linear Regression/Example notebook.ipynb | claury/sidecar-academy-batch2 |
Or by calling the method `.to_numpy()` : | np_array = df['x'].to_numpy()
print(np_array[:10]) | [-0.97468167 1.04349486 1.67141609 -0.05145155 1.98901715 1.69483221
2.3605217 3.69166478 1.80589394 1.55395614]
| MIT | S01 - Bootcamp and Binary Classification/SLU07 - Regression with Linear Regression/Example notebook.ipynb | claury/sidecar-academy-batch2 |
You can also apply this to the full table: | np_array = df.values
print(np_array[:5, :])
np_array = df.to_numpy()
print(np_array[:5, :]) | [[-9.74681670e-01 9.50004358e-01 -9.25951835e-01 -1.13819408e+00]
[ 1.04349486e+00 1.08888152e+00 1.13624227e+00 1.11665074e+00]
[ 1.67141609e+00 2.79363175e+00 4.66932106e+00 1.59111751e+00]
[-5.14515491e-02 2.64726191e-03 -1.36205726e-04 1.00102006e+00]
[ 1.98901715e+00 3.95618924e+00 7.86892827e+00 -9... | MIT | S01 - Bootcamp and Binary Classification/SLU07 - Regression with Linear Regression/Example notebook.ipynb | claury/sidecar-academy-batch2 |
a.2) Numpy to pandasLet's start by defining an array and converting it to a pandas series: | np_array = np.array([4., .1, 1., .23, 3.])
pd_series = pd.Series(np_array)
print(pd_series) | 0 4.00
1 0.10
2 1.00
3 0.23
4 3.00
dtype: float64
| MIT | S01 - Bootcamp and Binary Classification/SLU07 - Regression with Linear Regression/Example notebook.ipynb | claury/sidecar-academy-batch2 |
We can also create several series and concatenate them to create a dataframe: | np_array = np.array([4., .1, 1., .23, 3.])
pd_series_1 = pd.Series(np_array, name='A')
pd_series_2 = pd.Series(2 * np_array, name='B')
pd_dataframe = pd.concat((pd_series_1, pd_series_2), axis=1)
pd_dataframe.head() | _____no_output_____ | MIT | S01 - Bootcamp and Binary Classification/SLU07 - Regression with Linear Regression/Example notebook.ipynb | claury/sidecar-academy-batch2 |
We can also directly convert to a dataframe: | np_array = np.array([[1, 2, 3], [4, 5, 6]])
pd_dataframe = pd.DataFrame(np_array)
pd_dataframe.head() | _____no_output_____ | MIT | S01 - Bootcamp and Binary Classification/SLU07 - Regression with Linear Regression/Example notebook.ipynb | claury/sidecar-academy-batch2 |
However, we might want more detailed names and specific indices. Some ways of achieving this follows: | data = np.array([['','Col1','Col2'],
['Row1',1,2],
['Row2',3,4]])
pd_dataframe = pd.DataFrame(data=data[1:,1:], index=data[1:,0], columns=data[0,1:])
pd_dataframe.head()
pd_dataframe = pd.DataFrame(np.array([[4,5,6,7], [1,2,3,4]]), index=range(0, 2), columns=['A', 'B', '... | _____no_output_____ | MIT | S01 - Bootcamp and Binary Classification/SLU07 - Regression with Linear Regression/Example notebook.ipynb | claury/sidecar-academy-batch2 |
b) Vector and Matrix initialization and shapingWhen working with vectors and matrices, we need to be aware of the dimensions of these objects, and how they affect the possible operations perform over them. Numpy allows you to access these dimensions through the shape of the object: | v1 = np.array([ .1, 1., 2.])
print('1-d Array: {}'.format(v1))
print('Shape: {}'.format(v1.shape))
v2 = np.array([[ .1, 1., 2.]])
print('\n')
print('2-d Row Array: {}'.format(v2))
print('Shape: {}'.format(v2.shape))
v3 = np.array([[ .1], [1.], [2.]])
print('\n')
print('2-d Column Array:\n {}'.format(v3))
print(... | 1-d Array: [0.1 1. 2. ]
Shape: (3,)
2-d Row Array: [[0.1 1. 2. ]]
Shape: (1, 3)
2-d Column Array:
[[0.1]
[1. ]
[2. ]]
Shape: (3, 1)
2-d matrix:
[[0.1 3. 4. 1. ]
[1. 0.3 0.1 0.5]
[2. 0.7 3.8 0.1]]
Shape: (3, 4)
| MIT | S01 - Bootcamp and Binary Classification/SLU07 - Regression with Linear Regression/Example notebook.ipynb | claury/sidecar-academy-batch2 |
Another important functionality provided is the possibility of reshaping these objects. For example, we can turn a 1-d array into a row vector: | v1 = np.array([ .1, 1., 2.])
v1_reshaped = v1.reshape((1, -1))
print('Old 1-d Array reshaped to row: {}'.format(v1_reshaped))
print('Shape: {}'.format(v1_reshaped.shape))
| Old 1-d Array reshaped to row: [[0.1 1. 2. ]]
Shape: (1, 3)
| MIT | S01 - Bootcamp and Binary Classification/SLU07 - Regression with Linear Regression/Example notebook.ipynb | claury/sidecar-academy-batch2 |
Or we can reshape it into a column vector: | v1 = np.array([ .1, 1., 2.])
v1_reshaped = v2.reshape((-1, 1))
print('Old 1-d Array reshaped to column: \n{}'.format(v1_reshaped))
print('Shape: {}'.format(v1_reshaped.shape))
| Old 1-d Array reshaped to column:
[[0.1]
[1. ]
[2. ]]
Shape: (3, 1)
| MIT | S01 - Bootcamp and Binary Classification/SLU07 - Regression with Linear Regression/Example notebook.ipynb | claury/sidecar-academy-batch2 |
We can also create specific vectors of 1s, 0s or random numbers with specific shapes from the start. See how to use each in the cells that follow: | custom_shape = (3, )
v1_ones = np.ones(custom_shape)
print('1-D Vector of ones: \n{}'.format(v1_ones))
print('Shape: {}'.format(v1_ones.shape))
custom_shape = (5, 1)
v1_zeros = np.zeros(custom_shape)
print('2-D vector of zeros: \n{}'.format(v1_zeros))
print('Shape: {}... | 2-D Matrix of random numbers:
[[0.12203823 0.49517691 0.03438852]
[0.9093204 0.25877998 0.66252228]
[0.31171108 0.52006802 0.54671028]
[0.18485446 0.96958463 0.77513282]
[0.93949894 0.89482735 0.59789998]]
Shape: (5, 3)
| MIT | S01 - Bootcamp and Binary Classification/SLU07 - Regression with Linear Regression/Example notebook.ipynb | claury/sidecar-academy-batch2 |
c) Vector and Matrix Concatenation In this section, you will learn how to concatenate 2 vectors, a matrix and a vector, or 2 matrices. c.1) Vector - VectorLet's start by defining 2 vectors: | v1 = np.array([ .1, 1., 2.])
v2 = np.array([5.1, .3, .41, 3. ])
print('1st array: {}'.format(v1))
print('Shape: {}'.format(v1.shape))
print('2nd array: {}'.format(v2))
print('Shape: {}'.format(v2.shape)) | 1st array: [0.1 1. 2. ]
Shape: (3,)
2nd array: [5.1 0.3 0.41 3. ]
Shape: (4,)
| MIT | S01 - Bootcamp and Binary Classification/SLU07 - Regression with Linear Regression/Example notebook.ipynb | claury/sidecar-academy-batch2 |
Since vectors only have one dimension with a given size (notice the shape with only one element) we can only concatenate in this dimension, leading to a longer vector: | vconcat = np.concatenate((v1, v2))
print('Concatenated vector: {}'.format(vconcat))
print('Shape: {}'.format(vconcat.shape)) | Concatenated vector: [0.1 1. 2. 5.1 0.3 0.41 3. ]
Shape: (7,)
| MIT | S01 - Bootcamp and Binary Classification/SLU07 - Regression with Linear Regression/Example notebook.ipynb | claury/sidecar-academy-batch2 |
Concatenating vectors is very easy, and since we can only concatenate them in their one dimension, the sizes do not have to match. Now let's move on to a more complex case. c.2) Matrix - row vectorWhen concatenating matrices and vectors we have to take into account their dimensions. | v1 = np.array([ .1, 1., 2., 3.])
m1 = np.array([[5.1, .3, .41, 3. ], [5.1, .3, .41, 3. ]])
print('Array: {}'.format(v1))
print('Shape: {}'.format(v1.shape))
print('Matrix: \n{}'.format(m1))
print('Shape: {}'.format(m1.shape)) | Array: [0.1 1. 2. 3. ]
Shape: (4,)
Matrix:
[[5.1 0.3 0.41 3. ]
[5.1 0.3 0.41 3. ]]
Shape: (2, 4)
| MIT | S01 - Bootcamp and Binary Classification/SLU07 - Regression with Linear Regression/Example notebook.ipynb | claury/sidecar-academy-batch2 |
The first thing you need to know is that whatever numpy objects you are trying to concatenate need to have the same dimensions. Run the code below to verify that you can not concatenate directly the vector and matrix: | try:
vconcat = np.concatenate((v1, m1))
except Exception as e:
print('Concatenation raised the following error: {}'.format(e))
| Concatenation raised the following error: all the input arrays must have same number of dimensions, but the array at index 0 has 1 dimension(s) and the array at index 1 has 2 dimension(s)
| MIT | S01 - Bootcamp and Binary Classification/SLU07 - Regression with Linear Regression/Example notebook.ipynb | claury/sidecar-academy-batch2 |
So how can we do matrix-vector concatenation? It is actually quite simple. We'll use the reshape functionality you seen before to add a dimension to the vector. | v1_reshaped = v1.reshape((1, v1.shape[0]))
m1 = np.array([[5.1, .3, .41, 3. ], [5.1, .3, .41, 3. ]])
print('Array: {}'.format(v1_reshaped))
print('Shape: {}'.format(v1_reshaped.shape))
print('Matrix: \n{}'.format(m1))
print('Shape: {}'.format(m1.shape)) | Array: [[0.1 1. 2. 3. ]]
Shape: (1, 4)
Matrix:
[[5.1 0.3 0.41 3. ]
[5.1 0.3 0.41 3. ]]
Shape: (2, 4)
| MIT | S01 - Bootcamp and Binary Classification/SLU07 - Regression with Linear Regression/Example notebook.ipynb | claury/sidecar-academy-batch2 |
We've reshaped our vector into a 1-row matrix. Now we can try to perform the same concatenation: | vconcat = np.concatenate((v1_reshaped, m1))
print('Concatenated vector: {}'.format(vconcat))
print('Shape: {}'.format(vconcat.shape)) | Concatenated vector: [[0.1 1. 2. 3. ]
[5.1 0.3 0.41 3. ]
[5.1 0.3 0.41 3. ]]
Shape: (3, 4)
| MIT | S01 - Bootcamp and Binary Classification/SLU07 - Regression with Linear Regression/Example notebook.ipynb | claury/sidecar-academy-batch2 |
c.3) Matrix - column vector We can also do this procedure with a column vector: | v1 = np.array([ .1, 1.])
v1_reshaped = v1.reshape((v1.shape[0], 1))
m1 = np.array([[5.1, .3, .41, 3. ], [5.1, .3, .41, 3. ]])
print('Array: \n{}'.format(v1_reshaped))
print('Shape: {}'.format(v1_reshaped.shape))
print('Matrix: \n{}'.format(m1))
print('Shape: {}'.format(m1.shape))
vconcat = np.concatenate((v1_reshape... | Array:
[[0.1]
[1. ]]
Shape: (2, 1)
Matrix:
[[5.1 0.3 0.41 3. ]
[5.1 0.3 0.41 3. ]]
Shape: (2, 4)
Concatenated vector: [[0.1 5.1 0.3 0.41 3. ]
[1. 5.1 0.3 0.41 3. ]]
Shape: (2, 5)
| MIT | S01 - Bootcamp and Binary Classification/SLU07 - Regression with Linear Regression/Example notebook.ipynb | claury/sidecar-academy-batch2 |
There's yet another restriction when concatenating vectors and matrices. The dimension where we want to concatenate has to share the same size.See what would happen if we tried to concatenate a smaller vector with the same matrix: | v2 = np.array([ .1, 1.])
v2_reshaped = v2.reshape((1, v2.shape[0])) # Row vector as matrix
try:
vconcat = np.concatenate((v2, m1))
except Exception as e:
print('Concatenation raised the following error: {}'.format(e)) | Concatenation raised the following error: all the input arrays must have same number of dimensions, but the array at index 0 has 1 dimension(s) and the array at index 1 has 2 dimension(s)
| MIT | S01 - Bootcamp and Binary Classification/SLU07 - Regression with Linear Regression/Example notebook.ipynb | claury/sidecar-academy-batch2 |
c.4) Matrix - MatrixThis is just an extension of the previous case, since what we did before was transforming the vector into a matrix where the size of one of the dimensions is 1. So all the same restrictions apply, the arrays must have compatible dimensions. Run the following examples to see this: | m1 = np.array([[5.1, .3, .41, 3. ], [5.1, .3, .41, 3. ]])
m2 = np.array([[1., 2., 0., 3. ], [.1, .13, 1., 3. ], [.1, 2., .5, .3 ]])
m3 = np.array([[1., 0. ], [0., 1. ]])
print('Matrix 1: \n{}'.format(m1))
print('Shape: {}'.format(m1.shape))
print('Matrix 2: \n{}'.format(m2))
print('Shape: {}'.format(m2.shape))
prin... | Matrix 1:
[[5.1 0.3 0.41 3. ]
[5.1 0.3 0.41 3. ]]
Shape: (2, 4)
Matrix 2:
[[1. 2. 0. 3. ]
[0.1 0.13 1. 3. ]
[0.1 2. 0.5 0.3 ]]
Shape: (3, 4)
Matrix 3:
[[1. 0.]
[0. 1.]]
Shape: (2, 2)
| MIT | S01 - Bootcamp and Binary Classification/SLU07 - Regression with Linear Regression/Example notebook.ipynb | claury/sidecar-academy-batch2 |
Concatenate m1 and m2 at row level (stack the two matrices): | mconcat = np.concatenate((m1, m2))
print('Concatenated matrix:\n {}'.format(mconcat))
print('Shape: {}'.format(mconcat.shape)) | Concatenated matrix:
[[5.1 0.3 0.41 3. ]
[5.1 0.3 0.41 3. ]
[1. 2. 0. 3. ]
[0.1 0.13 1. 3. ]
[0.1 2. 0.5 0.3 ]]
Shape: (5, 4)
| MIT | S01 - Bootcamp and Binary Classification/SLU07 - Regression with Linear Regression/Example notebook.ipynb | claury/sidecar-academy-batch2 |
Concatenate m1 and m2 at column level (joining the two matrices side by side) should produce an error: | try:
vconcat = np.concatenate((m1, m2), axis=1)
except Exception as e:
print('Concatenation raised the following error: {}'.format(e))
| Concatenation raised the following error: all the input array dimensions for the concatenation axis must match exactly, but along dimension 0, the array at index 0 has size 2 and the array at index 1 has size 3
| MIT | S01 - Bootcamp and Binary Classification/SLU07 - Regression with Linear Regression/Example notebook.ipynb | claury/sidecar-academy-batch2 |
Concatenate m1 and m3 at column level (joining the two matrices side by side): | mconcat = np.concatenate((m1, m3), axis=1)
print('Concatenated matrix:\n {}'.format(mconcat))
print('Shape: {}'.format(mconcat.shape)) | Concatenated matrix:
[[5.1 0.3 0.41 3. 1. 0. ]
[5.1 0.3 0.41 3. 0. 1. ]]
Shape: (2, 6)
| MIT | S01 - Bootcamp and Binary Classification/SLU07 - Regression with Linear Regression/Example notebook.ipynb | claury/sidecar-academy-batch2 |
Concatenate m1 and m3 at row level (stack the two matrices) should produce an error: | try:
vconcat = np.concatenate((m1, m3))
except Exception as e:
print('Concatenation raised the following error: {}'.format(e))
| Concatenation raised the following error: all the input array dimensions for the concatenation axis must match exactly, but along dimension 1, the array at index 0 has size 4 and the array at index 1 has size 2
| MIT | S01 - Bootcamp and Binary Classification/SLU07 - Regression with Linear Regression/Example notebook.ipynb | claury/sidecar-academy-batch2 |
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