how to fit this simple mnist clasification - keras

this keras is a simple keras model, I use relu for simplicity and power of learning
also mean_square as a loss, but the model does not fit
I spect the output to be a number [0-9], im not using to_categorical, thas why there is only a output neuron
from keras.datasets import mnist
(data, labels),(x_test,y_test) = mnist.load_data()
from keras.layers import Input, Dense, Flatten
from keras.models import Model
from keras.losses import mean_squared_error
# This returns a tensor
inputs = Input(shape=(28, 28,))
x = Flatten()(inputs)
x = Dense(64, activation='relu')(x)
x = Dense(64, activation='relu')(x)
predictions = Dense(1, activation='relu')(x)
model = Model(inputs=inputs, outputs=predictions)
model.compile(optimizer='rmsprop',
loss=mean_squared_error,
metrics=['accuracy'])
model.fit(data, labels, batch_size=10, epochs=10 ,
validation_data=(x_test, y_test)) # starts training

Related

Keras LSTM to Pytorch

I am using the following code to apply sequential LSTM to time-series data with one value. It works fine with a Keras version. I am wondering how could I do the same using PyTorch?
import tensorflow
from tensorflow.keras import optimizers
from tensorflow.keras import losses
from tensorflow.keras.models import Sequential, Model
from tensorflow.keras.layers import Dense, Input, Dropout, Embedding, LSTM
from tensorflow.keras.optimizers import RMSprop, Adam, Nadam
from tensorflow.keras.preprocessing import sequence
from tensorflow.keras.callbacks import TensorBoard
# training_dataset.shape = (303, 24, 1)
time_steps = 24
metric = 'mean_absolute_error'
model = Sequential()
model.add(LSTM(units=32, activation='tanh', input_shape=(time_steps, 1), return_sequences=True))
model.add(Dense(1, activation='sigmoid'))
model.compile(optimizer='adam', loss='mean_absolute_error', metrics=[metric])
print(model.summary())
batch_size=32
epochs=20
model.fit(x=training_dataset, y=training_dataset,
batch_size=batch_size, epochs=epochs,
verbose=1, validation_data=(training_dataset, training_dataset),
callbacks=[TensorBoard(log_dir='../logs/{0}'.format(tensorlog))])
testing_pred = model.predict(x=testing_dataset)
You can check the pytorch documentation for that: https://pytorch.org/docs/master/generated/torch.nn.LSTM.html
the simplest code is the following:
import torch, torch.nn as nn, torch.optim.Adam as Adam
model = nn.Sequential(nn.LSTM(input_size=1, hidden_size=32, output_size=1), nn.Sigmoid)
opt = Adam(model.parameters())
loss_func = nn.MSELoss()
for (x, y) in dataloader:
opt.zero_grad()
pred = model(x)
loss = loss_func(y, pred)
loss.backward()
opt.step()

Transferlearning ResNet Model does not learn

I trained ResNet-50 model to classify images from 6 classes (my own dataset) and saved it. But the model did not learn properly and predictions are incorrect. What would be the reason for this poor learning?
Here is my code, and the output plots using Keras and TensorFlow backend. How can I solve this?
from keras.applications.resnet50 import ResNet50, preprocess_input
from keras.layers import Dense, Dropout
from keras.models import Model
from keras.optimizers import Adam, SGD
from keras.preprocessing.image import ImageDataGenerator, image
from keras.callbacks import EarlyStopping, ModelCheckpoint
from sklearn.metrics import confusion_matrix, classification_report, accuracy_score
from keras import backend as K
import numpy as np
import matplotlib.pyplot as plt
from PIL import ImageFile
ImageFile.LOAD_TRUNCATED_IMAGE = True
# Define some constant needed throughout the script
N_CLASSES = 6
EPOCHS = 20
PATIENCE = 5
TRAIN_PATH= '/Train/'
VALID_PATH = '/Test/'
MODEL_CHECK_WEIGHT_NAME = 'resnet_monki_v1_chk.h5'
# Define model to be used we freeze the pre trained resnet model weight, and add few layer on top of it to utilize our custom dataset
K.set_learning_phase(0)
model = ResNet50(input_shape=(224,224,3),include_top=False, weights='imagenet', pooling='avg')
K.set_learning_phase(1)
x = model.output
x = Dense(512, activation='relu')(x)
x = Dropout(0.5)(x)
x = Dense(512, activation='relu')(x)
x = Dropout(0.5)(x)
output = Dense(N_CLASSES, activation='softmax', name='custom_output')(x)
custom_resnet = Model(inputs=model.input, outputs = output)
for layer in model.layers:
layer.trainable = False
custom_resnet.compile(Adam(lr=0.001), loss='categorical_crossentropy', metrics=['accuracy'])
custom_resnet.summary()
# 4. Load dataset to be used
datagen = ImageDataGenerator(preprocessing_function=preprocess_input)
traingen = datagen.flow_from_directory(TRAIN_PATH, target_size=(224,224), batch_size=32, class_mode='categorical')
validgen = datagen.flow_from_directory(VALID_PATH, target_size=(224,224), batch_size=32, class_mode='categorical', shuffle=False)
# 5. Train Model we use ModelCheckpoint to save the best model based on validation accuracy
es_callback = EarlyStopping(monitor='val_acc', patience=PATIENCE, mode='max')
mc_callback = ModelCheckpoint(filepath=MODEL_CHECK_WEIGHT_NAME, monitor='val_acc', save_best_only=True, mode='max')
train_history = custom_resnet.fit_generator(traingen, steps_per_epoch=len(traingen), epochs= EPOCHS, validation_data=traingen, validation_steps=len(validgen), verbose=2, callbacks=[es_callback, mc_callback])
custom_resnet.save('custom_resnet.h5')
Here are the plots, I had to put the links, the site does not let me put a pic
enter image description here

How to find the wrong predictions in Keras?

I have built a Keras model for extracting information from a raw input of text input. I am getting an accuracy of 0.9869. How can I know which of the training data is making the accuracy go low? I have pasted the code I am using below.
import numpy as np
from keras.models import Model, load_model
from keras.layers import Input, Dense, LSTM, Activation, Bidirectional, Dot, Flatten
from keras.callbacks import ModelCheckpoint
x_nyha = np.load("data/x_nyha.npy")
y_nyha = np.load("data/y/y_nyha.npy")
print(x_nyha.shape)
print(y_nyha.shape)
input_shape = x_nyha.shape[1:3]
X = Input(shape=input_shape)
A = Bidirectional(LSTM(512, return_sequences=True), merge_mode='concat')(X)
D = Dense(900, activation='relu')(A)
E = Dense(1, activation='sigmoid')(D)
Y = Flatten()(E)
model = Model(X, Y)
model.summary()
model.compile(optimizer='adam', loss='binary_crossentropy', metrics=['accuracy'])
batch_size = 128
num_epochs = 50
model.fit(x_nyha, y_nyha, batch_size=batch_size, epochs=num_epochs, verbose=1)
I think that the easiest way will be the following: train model on training data, make predictions on training data and have a look at training samples where predictions are wrong.
An example of code:
model.fit(x_nyha, y_nyha, batch_size=batch_size, epochs=num_epochs, verbose=1)
prediction = np.round(model.predict(x_nyha))
wrong_predictions = x_nyha[prediction != y_nyha]
This way wrong_predictions contains rows, where your prediction as wrong.

MLP classifier_for multi class

I am newbie on keras,
I try to follow the Keras tutorial for Multilayer Perceptron (MLP) for multi-class softmax classification, using my data set.
My data has 3 classes and only one feature, but I don't understand why the result always show just 0,3 of accuracy and the model predicted all training data as first class. then the confusion matrix is like this.
Confusion matrix
Here the coding:
import keras
from keras.models import Sequential
from keras.layers import Dense, Dropout, Activation
from keras.optimizers import SGD
import pandas as pd
import numpy as np
# Importing the dataset
dataset = pd.read_csv('StatusAll.csv')
X = dataset.iloc[:, 1:].values
y = dataset.iloc[:, 0:1].values
# Splitting the dataset into the Training set and Test set
from sklearn.model_selection import train_test_split
x_train, x_test, y_train, y_test = train_test_split(X, y, test_size = 0.2, random_state = 0)
from keras.utils import to_categorical
y_train = to_categorical(y_train)
y_test = to_categorical(y_test)
model = Sequential()
# Dense(64) is a fully-connected layer with 64 hidden units.
# in the first layer, you must specify the expected input data shape:
# here, 20-dimensional vectors.
model.add(Dense(64, activation='tanh', input_dim=1))
model.add(Dropout(0.5))
model.add(Dense(64, activation='tanh'))
model.add(Dropout(0.5))
model.add(Dense(4, activation='softmax'))
sgd = SGD(lr=0.01, decay=1e-6, momentum=0.9, nesterov=True)
model.compile(loss='categorical_crossentropy',
optimizer=sgd,
metrics=['accuracy'])
history = model.fit(x_train, y_train,
epochs=100,
batch_size=128)
score = model.evaluate(x_test, y_test, batch_size=128)
print('Test score:', score[0])
print('Test accuracy:', score[1])
from sklearn import metrics
prediction = model.predict(x_test)
prediction = np.around(prediction)
y_test_non_category = [ np.argmax(t) for t in y_test ]
y_predict_non_category = [ np.argmax(t) for t in prediction ]
from sklearn.metrics import confusion_matrix
conf_mat = confusion_matrix(y_test_non_category, y_predict_non_category)
print (conf_mat)
I hope I can get some advice, thanksss.
The x_train example
x_train
y_train before converted to categorical
enter image description here
Your final Dense layer has 4 outputs, it seems like you are classifying 4 instead of 3.
model.add(Dense(3, activation='softmax')) # Number of classes 3
It would be helpful to see sample data from x_train and y_train to make sure the pre-processing is correct. Because you have only 1 feature, a MLP might be overkill. A decision tree would be simpler unless you want to experiment with MLPs.

Python- LSTM Based RNN error in input?

i am trying to build a deep learning network based on LSTM RNN
here is what is tried
from keras.models import Sequential
from keras.layers import Dense, Dropout, Activation
from keras.layers import Embedding
from keras.layers import LSTM
import numpy as np
train = np.loadtxt("TrainDatasetFinal.txt", delimiter=",")
test = np.loadtxt("testDatasetFinal.txt", delimiter=",")
y_train = train[:,7]
y_test = test[:,7]
train_spec = train[:,6]
test_spec = test[:,6]
model = Sequential()
model.add(LSTM(32, input_shape=(1415684, 8)))
model.add(LSTM(64, input_dim=1, input_length=1415684, return_sequences=True))
model.add(Dropout(0.5))
model.add(Dense(1))
model.add(Activation('sigmoid'))
model.compile(loss='binary_crossentropy', optimizer='rmsprop')
model.fit(train_spec, y_train, batch_size=2000, nb_epoch=11)
score = model.evaluate(test_spec, y_test, batch_size=2000)
but it gets me the following error
ValueError: Input 0 is incompatible with layer lstm_2: expected ndim=3, found ndim=2
Here is a sample from the dataset
(Patient Number, time in millisecond, accelerometer x-axis,y-axis, z-axis,magnitude, spectrogram,label (0 or 1))
1,15,70,39,-970,947321,596768455815000,0
1,31,70,39,-970,947321,612882670787000,0
1,46,60,49,-960,927601,602179976392000,0
1,62,60,49,-960,927601,808020878060000,0
1,78,50,39,-960,925621,726154800929000,0
in the dataset i am using the only the spectrogram as input feature and the label (0 or 1) as the output
the total traing samples is 1,415,684

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