initial commit

app.py

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+from matplotlib import pyplot as plt
+import numpy as np
+import streamlit as st
+import pandas as pd
+
+np.set_printoptions(precision=3)
+
+st.title("Eigen Values and Eigen Vectors")
+st.write(
+    "This app shows the effect of linear transformation with respect to eigen values and eigen vectors"
+)
+
+def getSquareY(x):
+    if x==-1 or x == 1:
+        return 0
+    else:
+        return 1
+
+getSquareYVectorised = np.vectorize(getSquareY)
+
+def getCircle(x):
+    return np.sqrt(1-np.square(x))
+
+with st.sidebar:
+    data = st.selectbox('Select type of dataset', ['Square', 'Circle'])
+    st.write("---")
+    st.text("Enter transformation matrix elements")
+    a_00 = st.slider(label = '$A_{0,0}$', min_value = -5, max_value=5, value=1)
+    a_01 = st.slider(label = '$A_{0,1}$', min_value = -5, max_value=5, value=0)
+    a_10 = st.slider(label = '$A_{1,0}$', min_value = -5, max_value=5, value=0)
+    a_11 = st.slider(label = '$A_{1,1}$', min_value = -5, max_value=5, value=1)
+
+def transform(x,y):
+    return a_00 * x + a_01 * y, a_10 * x + a_11 * y
+    
+
+x = np.linspace(-1,1,1000)
+y = getSquareYVectorised(x) if data == 'Square' else getCircle(x)
+
+x_dash_up, y_dash_up = transform(x,y)
+x_dash_down, y_dash_down = transform(x,-y)
+
+t = np.array([[a_00,a_01], [a_10, a_11]], dtype=np.float64)
+
+try:
+    evl, evec = np.linalg.eig(t)
+    fig, ax = plt.subplots()
+    ax.plot(x_dash_up,y_dash_up,'r')
+    ax.plot(x_dash_down,y_dash_down, 'g')
+    ax.quiver(0,0,evec[0][0],evec[0][1],scale=1,scale_units ='xy',angles='xy', facecolor='yellow', label='$\lambda_0$')
+    ax.quiver(0,0,evec[1][0],evec[1][1],scale=1,scale_units ='xy',angles='xy', facecolor='blue',label='$\lambda_1$')
+    ax.set_xlim(-5,5)
+    ax.set_ylim(-5,5)
+    ax.set_aspect('equal', adjustable='box')
+    fig.legend()
+    st.pyplot(fig)
+
+    df = pd.DataFrame({'Eigen Values': evl, 'Eigen Vectors': [str(evec[0]), str(evec[1])]})
+    st.table(df)
+except:
+    st.write("Given matrix has eigen vectors in complex space")

requirements.txt

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+matplotlib
+numpy
+pandas
+streamlit