Using a subset of tfrecord - tensorflow

Is it possible to use an existing tfrecord for one or a subset of the labels which was used to generate it
I'm training several models with the same data each would require only a one or a subset of labels used to originally create the tfrecord. The tfrecord is quite large so I want to about create one for each models subset of labels.

tf.data.Datasets have filter, skip and take methods which you may find useful. Alternatively you could split your original dataset across multiple tfrecord files and create a Dataset based on a subset of those files.
If you are happy to recreate the data using tensorflow_datasets, splits may also give you what you want.

Related

how to predict winner based on teammates

I am trying to create a machine learning model to predict the position of each team, but I am having trouble organizing the data in a way the model can train off of it.
I want the pandas dataframe to look something like this
Where each tournament has team members constantly shifting teams.
And based on the inputted teammates, the model makes a prediction on the team's position. Anyone have any suggestions on how I can make a pandas dataframe like this that a model can use as trainnig data? I'm completely stumped. Thanks in advance!
Coming on to the question as to how to create this sheet, you can easily get the data and store in the format you described above. The trick is in how to use it as training data to your model. We need to convert it in numerical form to be able to be used as training data to any model. As we know that the max team size is 3 in most cases, we can divide the three names in three columns (keep the column blank, if there are less than 3 members in the team). Now we can either use Label encoding or One-hot encoding to convert the names to numbers. You should create a combined list of all three columns to fit a LabelEncoder and then use transform function individually on each column (since the names might be shared in these 3 columns). On label encoding, we can easily use tree based models. One-hot encoding might lead to curse of dimensionality as there will be many names, so I would prefer not to use it for an initial simple model.

What is the difference between TFRecordDataset and FixedLengthRecordDataset?

It will be great to get a use case possibly from a project and explain the use of each. Thanks in advance.
TFRecordDataset, FixedLengthRecordDataset as well as TextLineDataset are classes of Dataset.
Dataset is a base class containing methods to create and transform datasets. Also allows you initialize a dataset from data in memory, or from a Python generator.
Since release 1.4, Datasets is a new way to create input pipelines to TensorFlow models. This API is much more performant than using feed_dict or the queue-based pipelines, and it's cleaner and easier to use.
As a use case, you can think of the pre-processing of data to feed it into a model for training (Examples in the links below are pretty self-explanatory).
TFRecordDataset: Reads records from TFRecord files (Example 1, Example 2).
#Python
dataset = tf.data.TFRecordDataset("/path/to/file.tfrecord")
FixedLengthRecordDataset: Reads fixed size records from binary files (Example).
#Python
images = tf.data.FixedLengthRecordDataset(
images_file, 28 * 28, header_bytes=16).map(decode_image)
TextLineDataset: Reads lines from text files.
See this documentation (TextLineDataset example included)

Number of distinct labels and input data shape in tf.data Dataset

The Tensorflow Fashion-MNIST tutorial is great... but it seems clear you have to know in advance that there are 10 distinct labels in the dataset, and that the input data is image data of size 28x28. I would have thought these details should be readily discoverable from the dataset itself - is this possible? Could I discover the same information the same way on a quite different dataset (e.g. the Titanic Dataset, which comprises M rows by N columns of CSV data, and is a binary classification task). tf.data.Dataset does not appear to have any obvious get_label_count() or get_input_shape() functions in its API. Call me a newbie, but this suprises/confuses me.
According to the accepted answer to this question, Tensorflow tf.data.Dataset instances are lazily evaluated, meaning that you could, in principle, need to iterate the through an entire dataset to establish the number of distinct labels, and the input data shape(s) (which can be variable, for example with variable-length sequences of sound or text).

What is the best way to feed the image+vector dataset to Tensorflow

I am trying to do a Deep Learning project by using Tensorflow.
Each of my data sets contains 2 files( PNGimage file + TXTvectors file ), where are put in different folders as follow:
./data/image/ #Folders contains different size of images
./data/vector/ #Folders contains vectors of corresponding image
#For example: apple.png + apple.txt
The example content of vector shows as follow:
10.0,2.5,5,13
And since image size are different, the resize and some transformation apply on vectors are required. It is important to make sure that I can do these processing during Tensorflow is running. Is there any good way to manage this kind of datasets?
I referred to a lot of basic tutorial however most of them are not so many details about arrange customized data input and output. Please give me some advice!
I recommend you to take a look at TFRecords and queues. Basically the idea is the following: you resize all your images to the same format and store them together with your txt vectors in one TFRecord file. This is done separately before you run your model.
When you create your model you create a queue which reads data from the TFRecord file and feeds it to your model.

Incorporating very large constants in Tensorflow

For example, the comments for the Tensorflow image captioning example model state:
NOTE: This script will consume around 100GB of disk space because each image
in the MSCOCO dataset is replicated ~5 times (once per caption) in the output.
This is done for two reasons:
1. In order to better shuffle the training data.
2. It makes it easier to perform asynchronous preprocessing of each image in
TensorFlow.
The primary goal of this question is to see if there is an alternative to this type of duplication. In my use case, storing the data in this way would require each image to be duplicated in the TFRecord files many more times, on the order of 20 - 50 times.
I should note first that I have already fed the images through VGGnet to extract 4096 dim features, and I have these stored as a mapping between filename and the vectors.
Before switching over to Tensorflow, I had been feeding batches containing filename strings and then looking up the corresponding vector on a per-batch basis. This allows me to store all of the image data in ~15GB without needing to duplicate the data on disk.
My first attempt to do this in in Tensorflow involved storing indices in the TFExample buffers and then doing a "preprocessing" step to slice into the corresponding matrix:
img_feat = pd.read_pickle("img_feats.pkl")
img_matrix = np.stack(img_feat)
preloaded_images = tf.Variable(img_matrix)
first_image = tf.slice(preloaded_images, [0,0], [1,4096])
However, in this case, Tensorflow disallows a variable larger than 2GB. So my next thought was to partition this across several variables:
img_tensors = []
for i in range(NUM_SPLITS):
with tf.Graph().as_default():
img_tensors.append(tf.Variable(img_matrices[i], name="preloaded_images_%i"%i))
first_image = tf.concat(1, [tf.slice(t, [0,0], [1,4096//NUM_SPLITS]) for t in img_tensors])
In this case, I'm forced to store each partition on a separate graph, because it seems any one graph cannot be this large either. However, now the concat fails because each tensor I am concatenating is on a separate graph.
Any advice on incorporating a large amount (~15GB) of preloaded into the Tensorflow graph.
Potentially related is this question; however in this case I'd like to override the decoding of the actual JPEG file with the preprocessed value in a tensor op.