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Convert Pandas dataframe to PyTorch tensor?

  • I want to train a simple neural network with PyTorch on a pandas dataframe df.

    One of the columns is named "Target", and it is the target variable of the network. How can I use this dataframe as input to the PyTorch network?

    I tried this, but it doesn't work:

    import pandas as pd
    import torch.utils.data as data_utils
    
    target = pd.DataFrame(df['Target'])
    train = data_utils.TensorDataset(df, target)
    train_loader = data_utils.DataLoader(train, batch_size=10, shuffle=True)

     

    This post was edited by Vaibhav Mali at December 16, 2021 12:57 PM IST
      December 16, 2021 12:57 PM IST
    0
  • You can use below functions to convert any dataframe or pandas series to a pytorch tensor

    import pandas as pd
    import torch
    
    # determine the supported device
    def get_device():
        if torch.cuda.is_available():
            device = torch.device('cuda:0')
        else:
            device = torch.device('cpu') # don't have GPU 
        return device
    
    # convert a df to tensor to be used in pytorch
    def df_to_tensor(df):
        device = get_device()
        return torch.from_numpy(df.values).float().to(device)
    
    df_tensor = df_to_tensor(df)
    series_tensor = df_to_tensor(series)
      December 27, 2021 1:31 PM IST
    0
  • I'm referring to the question in the title as you haven't really specified anything else in the text, so just converting the DataFrame into a PyTorch tensor.

    Without information about your data, I'm just taking float values as example targets here.

    Convert Pandas dataframe to PyTorch tensor?

    import pandas as pd
    import torch
    import random
    
    # creating dummy targets (float values)
    targets_data = [random.random() for i in range(10)]
    
    # creating DataFrame from targets_data
    targets_df = pd.DataFrame(data=targets_data)
    targets_df.columns = ['targets']
    
    # creating tensor from targets_df 
    torch_tensor = torch.tensor(targets_df['targets'].values)
    
    # printing out result
    print(torch_tensor)

    Output:

    tensor([ 0.5827,  0.5881,  0.1543,  0.6815,  0.9400,  0.8683,  0.4289,
             0.5940,  0.6438,  0.7514], dtype=torch.float64)

    Tested with Pytorch 0.4.0.

    I hope this helps, if you have any further questions - just ask. :)

     

     

      December 17, 2021 12:04 PM IST
    0
  • Maybe try this to see if it can fix your problem(based on your sample code)?

    train_target = torch.tensor(train['Target'].values.astype(np.float32))
    train = torch.tensor(train.drop('Target', axis = 1).values.astype(np.float32)) 
    train_tensor = data_utils.TensorDataset(train, train_target) 
    train_loader = data_utils.DataLoader(dataset = train_tensor, batch_size = batch_size, shuffle = True)
    
      December 20, 2021 12:09 PM IST
    0