My goal is to do grey scale image segmentation using pixelwise classification. So I have two labels 0 and 1. I made a network in pytorch which looks like the following.
class Net(nn.Module):
def __init__(self):
super(Net, self).__init__()
self.up = nn.Upsample(scale_factor=2, mode='nearest')
self.conv11 = nn.Conv2d(1, 128, kernel_size=3, padding=1)
self.conv12 = nn.Conv2d(128, 256, kernel_size=3, padding=1)
self.conv13 = nn.Conv2d(256, 2, kernel_size=3, padding=1)
def forward(self, x):
in_size = x.size(0)
x = F.relu(self.conv11(x))
x = F.relu(self.conv12(x))
x = F.relu(self.conv13(x))
x = F.softmax(x, 2)
return x
In the last layer I designed the conv13 in such that it produces 2 channels one for each class.
Since I was using the softmax I was expecting that summation of value of same index on 2 separate channel would equal to 1.
For example assume the output image is ( 2{channel}, 4, 4). So I was expecting that
image[ channel 1 ][0][0] + image[ channel 2 ][0][0] = 1
But the output I get is 0.0015 which is not even close to 1. How can i use the softmax to predict channelwise ?
To check this I used the following code
for batch, data in enumerate(trainloader, 0):
inputs , labels = data
inputs, labels = inputs.to(device), labels.to(device)
optimizer.zero_grad()
outputs = net(inputs)
loss = rmse(outputs, labels)
loss.backward()
optimizer.step()
running_loss += loss.item()
predicted = outputs.data
predicted = predicted.to('cpu')
predicted_img = predicted.numpy()
predicted_img = np.reshape(predicted_img,(2, 4, 4))
print(predicted_img[0])
print(predicted_img[1])
Those prints showed this
[[**0.2762002** 0.13305853 0.2510342 0.23114938]
[0.26812425 0.28500515 0.05682982 0.15851443]
[0.1640967 0.5409352 0.43547812 0.44782472]
[0.29157883 0.0410011 0.2566578 0.16251141]]
[[**0.23052207** 0.868455 0.43436486 0.0684725 ]
[0.18001427 0.02341573 0.0727293 0.2525512 ]
[0.06587404 0.04974682 0.3773188 0.6559266 ]
[0.5235896 0.05838248 0.11558701 0.02304965]]
It is clear that the corresponding elements are not summing up to 1 like
0.2762002 (index 0, 0) + 0.23052207 (index 0, 0) != 1
How can I fix it ?
Please check last line of my code .. basically your dimension for softmax was wrong.
class Net(nn.Module):
def __init__(self):
super(Net, self).__init__()
self.up = nn.Upsample(scale_factor=2, mode='nearest')
self.conv11 = nn.Conv2d(1, 128, kernel_size=3, padding=1)
self.conv12 = nn.Conv2d(128, 256, kernel_size=3, padding=1)
self.conv13 = nn.Conv2d(256, 2, kernel_size=3, padding=1)
def forward(self, x):
in_size = x.size(0)
x = F.relu(self.conv11(x))
x = F.relu(self.conv12(x))
x = F.relu(self.conv13(x))
x = F.softmax(x, 1) #this line is changed
return x
net = Net()
inputs = torch.rand(1,1,4,4)
out = net (Variable(inputs))
print (out)
out.sum(dim=1)
Hope that helps.
Related
I am new to tensor and trying to understand it. I managed to create one layer model. But I would like now to add 2 more. How can I make my train function working? I would like to train it with hundreds of values X and Y. I implemented all values what I need: Weight and Bias of each layer, but I dont understand how can I use them in my train function. And when it will be trained, how can I use it. Like I do in the last part of a code.
import numpy as np
print("TensorFlow version: {}".format(tf.__version__))
print("Eager execution: {}".format(tf.executing_eagerly()))
x = np.array([
[10, 10, 30, 20],
])
y = np.array([[10, 1, 1, 1]])
class Model(object):
def __init__(self, x, y):
# get random values.
self.W = tf.Variable(tf.random.normal((len(x), len(x[0]))))
self.b = tf.Variable(tf.random.normal((len(y),)))
self.W1 = tf.Variable(tf.random.normal((len(x), len(x[0]))))
self.b1 = tf.Variable(tf.random.normal((len(y),)))
self.W2 = tf.Variable(tf.random.normal((len(x), len(x[0]))))
self.b2 = tf.Variable(tf.random.normal((len(y),)))
def __call__(self, x):
out1 = tf.multiply(x, self.W) + self.b
out2 = tf.multiply(out1, self.W1) + self.b1
last_layer = tf.multiply(out2, self.W2) + self.b2
# Input_Leyer = self.W * x + self.b
return last_layer
def loss(predicted_y, desired_y):
return tf.reduce_sum(tf.square(predicted_y - desired_y))
optimizer = tf.optimizers.Adam(0.1)
def train(model, inputs, outputs):
with tf.GradientTape() as t:
current_loss = loss(model(inputs), outputs)
grads = t.gradient(current_loss, [model.W, model.b])
optimizer.apply_gradients(zip(grads, [model.W, model.b]))
print(current_loss)
model = Model(x, y)
for i in range(10000):
train(model, x, y)
for i in range(3):
InputX = np.array([
[input(), input(), input(), input()],
])
returning = tf.math.multiply(
InputX, model.W, name=None
)
print("I think that output can be:", returning)
Just add new variables to the list:
grads = t.gradient(current_loss, [model.W, model.b, model.W1, model.b1, model.W2, model.b2])
optimizer.apply_gradients(zip(grads, [model.W, model.b, model.W1, model.b1, model.W2, model.b2]))
I am trying to write my own custom loss function that is based on the false positive and negative rates. I made a dummy code so you can check the first 2 defenitions as well. I added the rest, so you can see how it is implemented. However, still somewhere the gradient turns out to be zero. What is now the step where the gradient turns zero, or how can I check this? Please I would like to know how I can fix this :).
I tried providing you with more information so you can play around as well, but if you miss anything please do let me know!
The gradient stays True during every step. However, still during the training of the model the loss is not updated, therefore the NN does not train.
y = Variable(torch.tensor((0, 0, 0, 1, 1,1), dtype=torch.float), requires_grad = True)
y_pred = Variable(torch.tensor((0.333, 0.2, 0.01, 0.99, 0.49, 0.51), dtype=torch.float), requires_grad = True)
x = Variable(torch.tensor((0, 0, 0, 1, 1,1), dtype=torch.float), requires_grad = True)
x_pred = Variable(torch.tensor((0.55, 0.25, 0.01, 0.99, 0.65, 0.51), dtype=torch.float), requires_grad = True)
def binary_y_pred(y_pred):
y_pred.register_hook(lambda grad: print(grad))
y_pred = y_pred+torch.tensor(0.5, requires_grad=True, dtype=torch.float)
y_pred = y_pred.pow(5) # this is my way working around using torch.where()
y_pred = y_pred.pow(10)
y_pred = y_pred.pow(15)
m = nn.Sigmoid()
y_pred = m(y_pred)
y_pred = y_pred-torch.tensor(0.5, requires_grad=True, dtype=torch.float)
y_pred = y_pred*2
y_pred.register_hook(lambda grad: print(grad))
return y_pred
def confusion_matrix(y_pred, y):
TP = torch.sum(y*y_pred)
TN = torch.sum((1-y)*(1-y_pred))
FP = torch.sum((1-y)*y_pred)
FN = torch.sum(y*(1-y_pred))
k_eps = torch.tensor(1e-12, requires_grad=True, dtype=torch.float)
FN_rate = FN/(TP + FN + k_eps)
FP_rate = FP/(TN + FP + k_eps)
return FN_rate, FP_rate
def dif_rate(FN_rate_y, FN_rate_x):
dif = (FN_rate_y - FN_rate_x).pow(2)
return dif
def custom_loss_function(y_pred, y, x_pred, x):
y_pred = binary_y_pred(y_pred)
FN_rate_y, FP_rate_y = confusion_matrix(y_pred, y)
x_pred= binary_y_pred(x_pred)
FN_rate_x, FP_rate_x = confusion_matrix(x_pred, x)
FN_dif = dif_rate(FN_rate_y, FN_rate_x)
FP_dif = dif_rate(FP_rate_y, FP_rate_x)
cost = FN_dif+FP_dif
return cost
# I added the rest so you can see how it is implemented, but this peace does not fully run well! If you want this part to run as well, I can add more code.
class FeedforwardNeuralNetModel(nn.Module):
def __init__(self, input_dim, hidden_dim, output_dim):
super(FeedforwardNeuralNetModel, self).__init__()
self.fc1 = nn.Linear(input_dim, hidden_dim)
self.relu1 = nn.ReLU()
self.fc2 = nn.Linear(hidden_dim, output_dim)
self.sigmoid = nn.Sigmoid()
def forward(self, x):
out = self.fc1(x)
out = self.relu1(out)
out = self.fc2(out)
out = self.sigmoid(out)
return out
model = FeedforwardNeuralNetModel(input_dim, hidden_dim, output_dim)
optimizer = torch.optim.Adam(model.parameters(), lr=0.0001, betas=[0.9, 0.99], amsgrad=True)
criterion = torch.nn.BCELoss(weight=None, size_average=None, reduce=None, reduction='mean')
for epoch in range(num_epochs):
train_err = 0
for i, (samples, truths) in enumerate(train_loader):
samples = Variable(samples)
truths = Variable(truths)
optimizer.zero_grad() # Reset gradients
outputs = model(samples) # Do the forward pass
loss2 = criterion(outputs, truths) # Calculate loss
samples_y = Variable(samples_y)
samples_x = Variable(samples_x)
y_pred = model(samples_y)
y = Variable(y, requires_grad=True)
x_pred = model(samples_x)
x= Variable(x, requires_grad=True)
cost = custom_loss_function(y_pred, y, x_pred, x)
loss = loss2*0+cost #checking only if cost works.
loss.backward()
optimizer.step()
train_err += loss.item()
train_loss.append(train_err)
I expect the model to update during training. There is no error message.
With your definitions:TP+FN=y and TN+FP=1-y. Then you'll get FN_rate=1-y_pred and FP_rate=y_pred. Your cost is then FN_rate+FP_rate=1, the gradient of which is 0.
You can check this by hand or using a library for symbolic mathematics (e.g., SymPy):
from sympy import symbols
y, y_pred = symbols("y y_pred")
TP = y * y_pred
TN = (1-y)*(1-y_pred)
FP = (1-y)*y_pred
FN = y*(1-y_pred)
# let's ignore the eps for now
FN_rate = FN/(TP + FN)
FP_rate = FP/(TN + FP)
cost = FN_rate + FP_rate
from sympy import simplify
print(simplify(cost))
# output: 1
I'm new to TF and ML.
Details about data: Features(x) - (70 x 70 x 70) tensor for each sample, y - a float for each sample.
TFRecords created with the following code:
def convert_to_tf_records():
def _bytes_feature(value):
return tf.train.Feature(bytes_list=tf.train.BytesList(value=[value]))
def _float64_feature(value):
return tf.train.Feature(float_list=tf.train.FloatList(value=[value]))
tfrecords_filename = 'A-100-h2-h2o.tfrecords'
writer = tf.python_io.TFRecordWriter(tfrecords_filename)
# Get data from db for now.
db = connect('results-60-70.db')
data = db.select(selection='Ti')
i = 0
for row in data:
desc = np.array(json.loads(row.descriptor), dtype=np.float32)
print(desc.shape)
be = float(row.binding_energy) * 23 # Convert to Kcal/mol ?
desc = desc.flatten()
desc = desc.tostring()
example = tf.train.Example(features=tf.train.Features(feature={'voxel_grid': _bytes_feature(desc), 'binding_energy': _float64_feature(be)}))
writer.write(example.SerializeToString())
i += 1
if i >= 10:
break
Input function:
def my_input_function(fname, perform_shuffle=False, repeat_count=None):
def _parse_elements(example):
features = tf.parse_single_example(example, features={'voxel_grid': tf.FixedLenFeature([], tf.string), 'binding_energy': tf.FixedLenFeature([], tf.float32)})
vg = tf.decode_raw(features['voxel_grid'], tf.float32)
vg = tf.reshape(vg, [70, 70, 70])
vg = tf.convert_to_tensor(vg, dtype=tf.float32)
vg = {'voxel_grid': vg}
e = tf.cast(features['binding_energy'], tf.float32)
return vg, e
def input_function():
dataset = tf.data.TFRecordDataset(fname).map(_parse_elements)
dataset = dataset.repeat(repeat_count)
dataset = dataset.batch(5)
dataset = dataset.prefetch(1)
if perform_shuffle:
dataset.shuffle(20)
iterator = dataset.make_one_shot_iterator()
batch_features, batch_labels = iterator.get_next()
return batch_features, batch_labels
return input_function
Model function:
def my_model_function(features, labels, mode):
if mode == tf.estimator.ModeKeys.PREDICT:
tf.logging.info("my_model_fn: PREDICT, {}".format(mode))
elif mode == tf.estimator.ModeKeys.EVAL:
tf.logging.info("my_model_fn: EVAL, {}".format(mode))
elif mode == tf.estimator.ModeKeys.TRAIN:
tf.logging.info("my_model_fn: TRAIN, {}".format(mode))
feature_columns = [tf.feature_column.numeric_column('voxel_grid', shape=(70, 70, 70), dtype=tf.float32)]
# Create the layer of input
input_layer = tf.feature_column.input_layer(features, feature_columns)
input_layer = tf.reshape(input_layer, [-1, 70, 70, 70, 1])
# Convolution layers
conv1 = tf.layers.conv3d(inputs=input_layer, strides=(2, 2, 2), filters=32, kernel_size=(7, 7, 7))
conv2 = tf.layers.conv3d(inputs=conv1, strides=(2, 2, 2), filters=32, kernel_size=(7, 7, 7))
pool3 = tf.layers.max_pooling3d(inputs=conv2, pool_size=[2, 2, 2], strides=2)
flat = tf.layers.flatten(pool3)
dense1 = tf.layers.dense(inputs=flat, units=10, activation=tf.nn.relu)
dense2 = tf.layers.dense(inputs=dense1, units=10, activation=tf.nn.relu)
output = tf.layers.dense(inputs=dense2, units=1)
predictions = {'binding_energy': output}
if mode == tf.estimator.ModeKeys.PREDICT:
return tf.estimator.EstimatorSpec(mode=mode, predictions=predictions)
# Calculate loss
loss = tf.losses.mean_squared_error(labels=labels, predictions=predictions)
if mode == tf.estimator.ModeKeys.TRAIN:
optimizer = tf.train.GradientDescentOptimizer(learning_rate=0.001)
train_op = optimizer.minimize(loss=loss, global_step=tf.train.get_global_step())
return tf.estimator.EstimatorSpec(mode=mode, loss=loss, train_op=train_op)
# Add evaluation metrics
eval_metric_ops = {"mse": tf.metrics.mean_squared_error(labels=labels, predictions=predictions['binding_energy'])}
if mode == tf.estimator.ModeKeys.EVAL:
return tf.estimator.EstimatorSpec(mode=mode, loss=loss, eval_metric_ops=eval_metric_ops)
When calling model.train using
model = tf.estimator.Estimator(model_fn=my_model_function, model_dir='./model_dir')
model.train(input_fn=my_input_function('A-100-h2-h2o.tfrecords'), steps=100)
I get the following error.
TypeError: Failed to convert object of type to Tensor.
Found it!
changing
# Calculate loss
loss = tf.losses.mean_squared_error(labels=labels, predictions=predictions)
to
# Calculate loss
loss = tf.losses.mean_squared_error(labels=labels, predictions=predictions['binding_energy'])
solves the issue.
I'm trying to make speech recognition system with tensorflow.
Input data is an numpy array of size 50000 X 1.
Output data (mapping data) is an numpy array of size 400 X 1.
Input and mapping data is passed in batches of 2 in a list.
I've used this tutorial to design the neural network. Following is the code snippet:
For RNN:
input_data = tf.placeholder(tf.float32, [batch_size, sound_constants.MAX_ROW_SIZE_IN_DATA, sound_constants.MAX_COLUMN_SIZE_IN_DATA], name="train_input")
target = tf.placeholder(tf.float32, [batch_size, sound_constants.MAX_ROW_SIZE_IN_TXT, sound_constants.MAX_COLUMN_SIZE_IN_TXT], name="train_output")
fwd_cell = tf.nn.rnn_cell.BasicLSTMCell(num_hidden, state_is_tuple=True, forget_bias=1.0)
# creating one backward cell
bkwd_cell = tf.nn.rnn_cell.BasicLSTMCell(num_hidden, state_is_tuple=True, forget_bias=1.0)
# creating bidirectional RNN
val, _, _ = tf.nn.static_bidirectional_rnn(fwd_cell, bkwd_cell, tf.unstack(input_data), dtype=tf.float32)
For feeding data:
feed = {g['input_data'] : trb[0], g['target'] : trb[1], g['dropout'] : 0.6}
accuracy_, _ = sess.run([g['accuracy'], g['ts']], feed_dict=feed)
accuracy += accuracy_
When I ran the code, I got this error:
Traceback (most recent call last):
File "/home/wolborg/PycharmProjects/speech-to-text-rnn/src/rnn_train_1.py", line 205, in <module>
tr_losses, te_losses = train_network(g)
File "/home/wolborg/PycharmProjects/speech-to-text-rnn/src/rnn_train_1.py", line 177, in train_network
accuracy_, _ = sess.run([g['accuracy'], g['ts']], feed_dict=feed)
File "/home/wolborg/anaconda2/lib/python2.7/site-packages/tensorflow/python/client/session.py", line 895, in run
run_metadata_ptr)
File "/home/wolborg/anaconda2/lib/python2.7/site-packages/tensorflow/python/client/session.py", line 1102, in _run
raise ValueError('Tensor %s may not be fed.' % subfeed_t)
ValueError: Tensor Tensor("Const:0", shape=(), dtype=float32) may not be fed.
Process finished with exit code 1
Earlier, I was facing this issue with tf.sparse_placeholder, then after some browsing, I changed input type to tf.placeholder and made related changes. Now I'm clueless on where I'm making the error.
Please suggest something as how should I feed data.
Entire code:
import tensorflow as tf
# for taking MFCC and label input
import numpy as np
import rnn_input_data_1
import sound_constants
# input constants
# Training Parameters
num_input = 10 # mfcc data input
training_data_size = 8 # determines number of files in training and testing module
testing_data_size = num_input - training_data_size
# Network Parameters
learning_rate = 0.0001 # for large training set, it can be set 0.001
num_hidden = 200 # number of hidden layers
num_classes = 28 # total alphabet classes (a-z) + extra symbols (', ' ')
epoch = 1 # number of iterations
batch_size = 2 # number of batches
mfcc_coeffs, text_data = rnn_input_data_1.mfcc_and_text_encoding()
class DataGenerator:
def __init__(self, data_size):
self.ptr = 0
self.epochs = 0
self.data_size = data_size
def next_batch(self):
self.ptr += batch_size
if self.ptr > self.data_size:
self.epochs += 1
self.ptr = 0
return mfcc_coeffs[self.ptr-batch_size : self.ptr], text_data[self.ptr-batch_size : self.ptr]
def reset_graph():
if 'sess' in globals() and sess:
sess.close()
tf.reset_default_graph()
def struct_network():
print ('Inside struct network !!')
reset_graph()
input_data = tf.placeholder(tf.float32, [batch_size, sound_constants.MAX_ROW_SIZE_IN_DATA, sound_constants.MAX_COLUMN_SIZE_IN_DATA], name="train_input")
target = tf.placeholder(tf.float32, [batch_size, sound_constants.MAX_ROW_SIZE_IN_TXT, sound_constants.MAX_COLUMN_SIZE_IN_TXT], name="train_output")
keep_prob = tf.constant(1.0)
fwd_cell = tf.nn.rnn_cell.BasicLSTMCell(num_hidden, state_is_tuple=True, forget_bias=1.0)
# creating one backward cell
bkwd_cell = tf.nn.rnn_cell.BasicLSTMCell(num_hidden, state_is_tuple=True, forget_bias=1.0)
# creating bidirectional RNN
val, _, _ = tf.nn.static_bidirectional_rnn(fwd_cell, bkwd_cell, tf.unstack(input_data), dtype=tf.float32)
# adding dropouts
val = tf.nn.dropout(val, keep_prob)
val = tf.transpose(val, [1, 0, 2])
last = tf.gather(val, int(val.get_shape()[0]) - 1)
# creating bidirectional RNN
print ('BiRNN created !!')
print ('Last Size: ', last.get_shape())
weight = tf.Variable(tf.truncated_normal([num_hidden * 2, sound_constants.MAX_ROW_SIZE_IN_TXT]))
bias = tf.Variable(tf.constant(0.1, shape=[sound_constants.MAX_ROW_SIZE_IN_TXT]))
# mapping to 28 output classes
logits = tf.matmul(last, weight) + bias
prediction = tf.nn.softmax(logits)
prediction = tf.reshape(prediction, shape = [batch_size, sound_constants.MAX_ROW_SIZE_IN_TXT, sound_constants.MAX_COLUMN_SIZE_IN_TXT])
# getting probability distribution
mat1 = tf.cast(tf.argmax(prediction,1),tf.float32)
correct = tf.equal(prediction, target)
accuracy = tf.reduce_mean(tf.cast(correct, tf.float32))
logits = tf.reshape(logits, shape=[batch_size, sound_constants.MAX_ROW_SIZE_IN_TXT, sound_constants.MAX_COLUMN_SIZE_IN_TXT])
loss = tf.reduce_mean(tf.nn.softmax_cross_entropy_with_logits(logits=logits, labels=target))
train_step = tf.train.AdamOptimizer(1e-4).minimize(loss)
# returning components as dictionary elements
return {'input_data' : input_data,
'target' : target,
'dropout': keep_prob,
'loss': loss,
'ts': train_step,
'preds': prediction,
'accuracy': accuracy
}
def train_network(graph):
# initialize tensorflow session and all variables
# tf_gpu_config = tf.ConfigProto(allow_soft_placement = True, log_device_placement = True)
# tf_gpu_config.gpu_options.allow_growth = True
# with tf.Session(config = tf_gpu_config) as sess:
with tf.Session() as sess:
train_instance = DataGenerator(training_data_size)
test_instance = DataGenerator(testing_data_size)
print ('Training data size: ', train_instance.data_size)
print ('Testing data size: ', test_instance.data_size)
sess.run(tf.global_variables_initializer())
print ('Starting session...')
step, accuracy = 0, 0
tr_losses, te_losses = [], []
current_epoch = 0
while current_epoch < epoch:
step += 1
trb = train_instance.next_batch()
feed = {g['input_data'] : trb[0], g['target'] : trb[1], g['dropout'] : 0.6}
accuracy_, _ = sess.run([g['accuracy'], g['ts']], feed_dict=feed)
accuracy += accuracy_
if train_instance.epochs > current_epoch:
current_epoch += 1
tr_losses.append(accuracy / step)
step, accuracy = 0, 0
#eval test set
te_epoch = test_instance.epochs
while test_instance.epochs == te_epoch:
step += 1
print ('Testing round ', step)
trc = test_instance.next_batch()
feed = {g['input_data']: trc[0], g['target']: trc[1]}
accuracy_ = sess.run([g['accuracy']], feed_dict=feed)[0]
accuracy += accuracy_
te_losses.append(accuracy / step)
step, accuracy = 0,0
print("Accuracy after epoch", current_epoch, " - tr:", tr_losses[-1], "- te:", te_losses[-1])
return tr_losses, te_losses
g = struct_network()
tr_losses, te_losses = train_network(g)
You defined keep_prob as a tf.constant, but then trying to feed the value into it. Replace keep_prob = tf.constant(1.0) with keep_prob = tf.placeholder(tf.float32,[]) or keep_prob = tf.placeholder_with_default(1.0,[])
I am using wx.python along with VPython to make an orbit simulator, however i'm having trouble trying to get the sliders in the GUI to effect the simulation, I assume it's because I am trying to get the number associated with the slider button to go into a while loop when it is running.
So my question is, how do i get the function SetRate to update in the while loop located at the bottom of the code? (I have checked to see that the slider is retuning values)
Here is my code for reference:
Value = 1.0
dt = 100.0
def InputValue(Value):
dt = Value
def SetRate(evt):
global Value
Value = SpeedOfSimulation.GetValue()
return Value
w = window(menus=True, title="Planetary Orbits",x=0, y=0, width = 1000, height = 1000)
Screen = display(window = w, x = 30, y = 30, width = 700, height = 500)
gdisplay(window = w, x = 80, y = 80 , width = 40, height = 20)
p = w.panel # Refers to the full region of the window in which to place widgets
SpeedOfSimulation = wx.Slider(p, pos=(800,10), size=(200,100), minValue=0, maxValue=1000)
SpeedOfSimulation.Bind(wx.EVT_SCROLL, SetRate)
TestData = [2, 0, 0, 0, 6371e3, 5.98e24, 0, 0, 0, 384400e3, 0, 0, 1737e3, 7.35e22, 0, 1e3, 0]
Nstars = TestData[0] # change this to have more or fewer stars
G = 6.7e-11 # Universal gravitational constant
# Typical values
Msun = 2E30
Rsun = 2E9
vsun = 0.8*sqrt(G*Msun/Rsun)
Stars = []
colors = [color.red, color.green, color.blue,
color.yellow, color.cyan, color.magenta]
PositionList = []
MomentumList = []
MassList = []
RadiusList = []
for i in range(0,Nstars):
s=i*8
x = TestData[s+1]
y = TestData[s+2]
z = TestData[s+3]
Radius = TestData[s+4]
Stars = Stars+[sphere(pos=(x,y,z), radius=Radius, color=colors[i % 6],
make_trail=True, interval=10)]
Mass = TestData[s+5]
SpeedX = TestData[s+6]
SpeedY = TestData[s+7]
SpeedZ = TestData[s+8]
px = Mass*(SpeedX)
py = Mass*(SpeedY)
pz = Mass*(SpeedZ)
PositionList.append((x,y,z))
MomentumList.append((px,py,pz))
MassList.append(Mass)
RadiusList.append(Radius)
pos = array(PositionList)
Momentum = array(MomentumList)
Mass = array(MassList)
Mass.shape = (Nstars,1) # Numeric Python: (1 by Nstars) vs. (Nstars by 1)
Radii = array(RadiusList)
vcm = sum(Momentum)/sum(Mass) # velocity of center of mass
Momentum = Momentum-Mass*vcm # make total initial momentum equal zero
Nsteps = 0
time = clock()
Nhits = 0
while True:
InputValue(Value) #Reprensents the change in time
rate(100000) #No more than 100 loops per second on fast computers
# Compute all forces on all stars
r = pos-pos[:,newaxis] # all pairs of star-to-star vectors (Where r is the Relative Position Vector
for n in range(Nstars):
r[n,n] = 1e6 # otherwise the self-forces are infinite
rmag = sqrt(sum(square(r),-1)) # star-to-star scalar distances
hit = less_equal(rmag,Radii+Radii[:,newaxis])-identity(Nstars)
hitlist = sort(nonzero(hit.flat)[0]).tolist() # 1,2 encoded as 1*Nstars+2
F = G*Mass*Mass[:,newaxis]*r/rmag[:,:,newaxis]**3 # all force pairs
for n in range(Nstars):
F[n,n] = 0 # no self-forces
Momentum = Momentum+sum(F,1)*dt
# Having updated all momenta, now update all positions
pos = pos+(Momentum/Mass)*dt
# Update positions of display objects; add trail
for i in range(Nstars):
Stars[i].pos = pos[i]
I know nothing about vpython but in a normal wxPython app, you will use wx.Timer instead of while loop.
here is an example of wx.Timer modified from https://www.blog.pythonlibrary.org/2009/08/25/wxpython-using-wx-timers/
You will want to separate the while loop part from your SetRate class method and put it in update.
import wx
class MyForm(wx.Frame):
def __init__(self):
wx.Frame.__init__(self, None, wx.ID_ANY, "Timer Tutorial 1",
size=(500,500))
# Add a panel so it looks the correct on all platforms
panel = wx.Panel(self, wx.ID_ANY)
self.timer = wx.Timer(self)
self.Bind(wx.EVT_TIMER, self.update, self.timer)
SpeedOfSimulation = wx.Slider(p, pos=(800,10), size=(200,100), minValue=0, maxValue=1000)
SpeedOfSimulation.Bind(wx.EVT_SCROLL, SetRate)
self.SpeedOfSimulation = SpeedOfSimulation
def update(self, event):
# Compute all forces on all stars
SpeedOfSimulation = self.SpeedOfSimulation.GetValue()