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How to pass values from list to scikit learn linear regression model?

I have imported values into python from a PostgreSQL DB.
data = cur.fetchall()
The list is like this:-
[('Ending Crowds', 85, Decimal('50.49')), ('Salute Apollo', 73, Decimal('319.93'))][0]
I need to give 85 as X & Decimal('50.49') as Y in LinearRegression model
Then I imported packages & class-
import numpy as np
import pandas as pd
from sklearn.linear_model import LinearRegression
I provide data & perform linear regression -
X = data.iloc[:, 1].values.reshape(-1, 1)
Y = data.iloc[:, 2].values.reshape(-1, 1)
linear_regressor = LinearRegression() # create object for the class
linear_regressor.fit(X, Y) # perform linear regression
I am getting the error-
AttributeError: 'list' object has no attribute 'iloc'
I am a beginner to pyhon and started just 2 days back but need to do linear regression in python at my job for a project. I think iloc can't be used for list object. But, not able to figure out as to how to pass on X & Y values to linear_regressor. All the examples performing Linear Regression on sites are using .CSV. Please help me out.

No, you can't use .iloc on 'list', it is for dataframe.
convert it into dataframe and try using .iloc
Your solution is below, please approve it if it is correct.
Because it's my 1st answer on StackOverflow
import pandas as pd
from decimal import Decimal
from sklearn.linear_model import LinearRegression
#I don't know what that "[0]" in your list,because I haven't used data fetched from PostgreSQL. Anyway remove it first and store it in temp
temp=[('Ending Crowds', 85, Decimal('50.49')), ('Salute Apollo', 73, Decimal('319.93'))]
#I don't know it really needed or not
var = list(var)
data = []
#It is to remove "Decimal" word
for row in var:
data.append(list(map(str, list(row))))
data=pd.DataFrame(data,columns=["no_use","X","Y"])
X=data['X'].values.reshape(-1, 1)
Y=data['Y'].values.reshape(-1, 1)
print(X,Y)
linear_regressor = LinearRegression() # create object for the class
linear_regressor.fit(X, Y) # perform linear regression

Bad Input Shape

I don't know that my code is correct or not. but I got the error:
bad input shape (1, 301)
from sklearn import svm
import pandas as pd
clf = svm.SVC(gamma='scale')
df = pd.read_csv('C:\\Users\\Armin\\Desktop\\heart.csv')
x = [df.age[1:302], df.sex[1:302], df.cp[1:302], df.trestbps[1:302], df.chol[1:302], df.fbs[1:302], df.restecg[1:302], df.thalach[1:302], df.exang[1:302], df.oldpeak[1:302], df.slope[1:302], df.ca[1:302], df.thal[1:302]]
y = [df.target[1:302]]
clf.fit(x, y)

This is a very simple fix.
You need all the columns from df in x except the target column, for that, just do:
x = df.drop('target', axis=1)
And your target column will be:
y = df['target']
And now do your fit:
clf.fit(x, y)
It will work.
PS: What you were trying to do is passing list of Series having the features value. But what you just need to do is, pass the actual values of your feature set and targets from the dataframe directly.
Some more references for you to get started and keep going:
Read more about what to pass to the fit method here: https://scikit-learn.org/stable/modules/generated/sklearn.svm.SVC.html#sklearn.svm.SVC.fit
Here is a super basic tutorial from the folks of scikit themselves: https://scikit-learn.org/stable/tutorial/basic/tutorial.html

MLPClassifier: Expected 2D array got 1D array instead

Sup guys, I'm new to Python and new to Neural Networks as well. I'm trying to implement a Neural Network to predict the Close price of Bitcoin in a day, based on Open price in the same day. So I get a CSV file, and I'm trying to use 'Open' column as entry, and 'Close' column as target, you can see this in the code below:
from sklearn.neural_network import MLPClassifier
import numpy as np
import pandas as pd
dataset = pd.read_csv('BTC_USD.csv')
X = dataset['Open']
y = dataset['Close']
NeuralNetwork = MLPClassifier(verbose = True,
max_iter = 1000,
tol = 0,
activation = 'logistic')
NeuralNetwork.fit(X, y)
When I run the code I get this error:
ValueError: Expected 2D array, got 1D array instead:
array=[4.95100000e-02 4.95100000e-02 8.58400000e-02 ... 6.70745996e+03
6.66883984e+03 7.32675977e+03].
Reshape your data either using array.reshape(-1, 1) if your data has a single feature or array.reshape(1, -1) if it contains a single sample.
After this error, I did some research here in stackoverflow, and I tried some solutions proposed in other posts, like this one:
from sklearn.neural_network import MLPClassifier
import numpy as np
import pandas as pd
dataset = pd.read_csv('BTC_USD.csv')
X = np.array(dataset[['Open']])
X = X.reshape(-1, 1)
y = np.array(dataset[['Close']])
y = y.reshape(-1, 1)
NeuralNetwork = MLPClassifier(verbose = True,
max_iter = 1000,
tol = 0,
activation = 'logistic')
NeuralNetwork.fit(X, y)
After running this code, I get this new error:
ValueError: Unknown label type: (array([4.95100000e-02, 8.58400000e-02, 8.08000000e-02, ...,
6.66883984e+03, 6.30685010e+03, 7.49379980e+03]),)
and this ''warning'' at the first line (which contains the directory):
DataConversionWarning: A column-vector y was passed when a 1d array was expected. Please change the shape of y to (n_samples, ), for example using ravel().
y = column_or_1d(y, warn=True)
Could you help me please? I tried many solutions, but any of them worked.

You should use the values attribute of a data frame to get the elements of one column. In addition, what you want to achieve is a regression, not a classification, thus you must use a regressor such as MLPRegressor, following
from sklearn.neural_network import MLPRegressor
import numpy as np
import pandas as pd
dataset = pd.read_csv('BTC_USD.csv')
X = dataset["Open"].values.reshape(-1, 1)
y = dataset["Close"].values
NeuralNetwork = MLPRegressor(verbose = True,
max_iter = 1000,
tol = 0,
activation = "logistic")
NeuralNetwork.fit(X, y)
The code works now, but the results are not correct as you will need to work on the features and your network hyperparameters. But this is beyond the scope of SO.

LinearDiscriminantAnalysis - Single column output from .transform(X)

I have been successfully playing around with replicating one of the sklearn tutorials using the iris dataset in PyCharm using Python 2.7. However, when trying to repeat this with my own data I have been encountering an issue. I have been importing data from a .csv file using 'np.genfromtxt', but for some reason I keep getting a single column output for X_r2 (see below), when I should get a 2 column output. I have therefore replaced my data with some randomly generated variables to post onto SO, and I am still getting the same issue.
I have included the 'problem' code below, and I would be interested to know what I have done wrong. I have extensively used the debugging features in PyCharm to check that the type and shape of my variables are similar to the original sklearn example, but it did not help me with the problem. Any help or suggestions would be appreciated.
import numpy as np
from sklearn.discriminant_analysis import LinearDiscriminantAnalysis
y = np.random.randint(2, size=500)
X = np.random.randint(1, high=1000, size=(500, 6))
target_names = np.array([['XX'], ['YY']])
lda = LinearDiscriminantAnalysis(n_components=2)
X_r2 = lda.fit(X, y).transform(X)

The array y in the example you posted has values of 0, 1 and 2 while yours only has values of 0 and 1. This change achieves what you want:
import numpy as np
from sklearn.discriminant_analysis import LinearDiscriminantAnalysis
y = np.random.randint(3, size=500)
X = np.random.randint(1, high=1000, size=(500, 6))
target_names = np.array([['XX'], ['YY']])
lda = LinearDiscriminantAnalysis(n_components=2)
X_r2 = lda.fit(X, y).transform(X)

Linear Regression on Pandas DataFrame using Sklearn ( IndexError: tuple index out of range)

I'm new to Python and trying to perform linear regression using sklearn on a pandas dataframe. This is what I did:
data = pd.read_csv('xxxx.csv')
After that I got a DataFrame of two columns, let's call them 'c1', 'c2'. Now I want to do linear regression on the set of (c1,c2) so I entered
X=data['c1'].values
Y=data['c2'].values
linear_model.LinearRegression().fit(X,Y)
which resulted in the following error
IndexError: tuple index out of range
What's wrong here? Also, I'd like to know
visualize the result
make predictions based on the result?
I've searched and browsed a large number of sites but none of them seemed to instruct beginners on the proper syntax. Perhaps what's obvious to experts is not so obvious to a novice like myself.
Can you please help? Thank you very much for your time.
PS: I have noticed that a large number of beginner questions were down-voted in stackoverflow. Kindly take into account the fact that things that seem obvious to an expert user may take a beginner days to figure out. Please use discretion when pressing the down arrow lest you'd harm the vibrancy of this discussion community.

Let's assume your csv looks something like:
c1,c2
0.000000,0.968012
1.000000,2.712641
2.000000,11.958873
3.000000,10.889784
...
I generated the data as such:
import numpy as np
from sklearn import datasets, linear_model
import matplotlib.pyplot as plt
length = 10
x = np.arange(length, dtype=float).reshape((length, 1))
y = x + (np.random.rand(length)*10).reshape((length, 1))
This data is saved to test.csv (just so you know where it came from, obviously you'll use your own).
data = pd.read_csv('test.csv', index_col=False, header=0)
x = data.c1.values
y = data.c2.values
print x # prints: [ 0. 1. 2. 3. 4. 5. 6. 7. 8. 9.]
You need to take a look at the shape of the data you are feeding into .fit().
Here x.shape = (10,) but we need it to be (10, 1), see sklearn. Same goes for y. So we reshape:
x = x.reshape(length, 1)
y = y.reshape(length, 1)
Now we create the regression object and then call fit():
regr = linear_model.LinearRegression()
regr.fit(x, y)
# plot it as in the example at http://scikit-learn.org/
plt.scatter(x, y, color='black')
plt.plot(x, regr.predict(x), color='blue', linewidth=3)
plt.xticks(())
plt.yticks(())
plt.show()
See sklearn linear regression example.

Dataset
Importing the libraries
import numpy as np
import matplotlib.pyplot as plt
import pandas as pd
from sklearn.linear_model import LinearRegression
Importing the dataset
dataset = pd.read_csv('1.csv')
X = dataset[["mark1"]]
y = dataset[["mark2"]]
Fitting Simple Linear Regression to the set
regressor = LinearRegression()
regressor.fit(X, y)
Predicting the set results
y_pred = regressor.predict(X)
Visualising the set results
plt.scatter(X, y, color = 'red')
plt.plot(X, regressor.predict(X), color = 'blue')
plt.title('mark1 vs mark2')
plt.xlabel('mark1')
plt.ylabel('mark2')
plt.show()

I post an answer that addresses exactly the error that you got:
IndexError: tuple index out of range
Scikit-learn expects 2D inputs. Just reshape the X and Y.
Replace:
X=data['c1'].values # this has shape (XXX, ) - It's 1D
Y=data['c2'].values # this has shape (XXX, ) - It's 1D
linear_model.LinearRegression().fit(X,Y)
with
X=data['c1'].values.reshape(-1,1) # this has shape (XXX, 1) - it's 2D
Y=data['c2'].values.reshape(-1,1) # this has shape (XXX, 1) - it's 2D
linear_model.LinearRegression().fit(X,Y)

make predictions based on the result?
To predict,
lr = linear_model.LinearRegression().fit(X,Y)
lr.predict(X)
Is there any way I can view details of the regression?
The LinearRegression has coef_ and intercept_ attributes.
lr.coef_
lr.intercept_
show the slope and intercept.

You really should have a look at the docs for the fit method which you can view here
For how to visualize a linear regression, play with the example here. I'm guessing you haven't used ipython (Now called jupyter) much either, so you should definitely invest some time into learning that. It's a great tool for exploring data and machine learning. You can literally copy/paste the example from scikit linear regression into an ipython notebook and run it
For your specific problem with the fit method, by referring to the docs, you can see that the format of the data you are passing in for your X values is wrong.
Per the docs,
"X : numpy array or sparse matrix of shape [n_samples,n_features]"
You can fix your code with this
X = [[x] for x in data['c1'].values]