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--- |
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license: cc0-1.0 |
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task_categories: |
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- image-classification |
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- clustering |
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tags: |
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- mnist |
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- digits |
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- computer-vision |
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- machine-learning |
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- matlab |
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dataset_info: |
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features: |
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- name: data |
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dtype: uint8 |
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shape: [784] |
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- name: labels |
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dtype: uint8 |
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splits: |
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- name: train |
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num_bytes: 3170000000 |
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num_examples: 8100000 |
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--- |
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# MNIST8M Dataset (.mat format) |
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## Dataset Description |
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This repository contains the MNIST8M dataset converted to MATLAB `.h5` format for convenient use in MATLAB environments. The original data is sourced from the LIBSVM datasets page. |
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### Dataset Summary |
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- **Original Source**: [LIBSVM Multiclass Datasets - MNIST8M](https://www.csie.ntu.edu.tw/~cjlin/libsvmtools/datasets/multiclass.html#mnist8m) |
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- **Format Conversion**: Converted from original LibSVM format to MATLAB `.h5` format |
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- **Purpose**: Facilitate clustering and machine learning experiments in MATLAB |
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- **Files**: `MNIST8M_data.h5`, `labels.mat` |
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### Data Specifications |
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- **Samples**: 8,100,000 (8.1 million) |
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- **Features**: 784 (28×28 pixel images) |
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- **Data Type**: `uint8` |
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- **Value Range**: [0, 255] |
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- **Labels**: 10 classes (digits 0-9) |
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- **Label Type**: `uint8` |
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- **Label Range**: [0, 9] |
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### Storage Format |
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- `MNIST8M_data`: uint8 matrix of size 8,100,000 × 784 |
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- `labels`: uint8 vector of size 8,100,000 × 1 |
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### Usage Warning |
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⚠️ **Memory Considerations**: Loading the entire dataset directly into memory may cause out-of-memory errors on systems with insufficient RAM. The uncompressed data requires approximately 6GB of memory (8.1M × 784 × 1 byte). |
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### Recommended Usage |
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For systems with limited memory, consider: |
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- Loading data in batches |
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- Using memory-mapped files |
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- Working with data subsets |
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- Converting to single precision when possible |
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### Source Attribution |
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Original dataset courtesy of: |
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- [LIBSVM Datasets](https://www.csie.ntu.edu.tw/~cjlin/libsvmtools/datasets/multiclass.html#mnist8m) |
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- [infinite MNIST](https://leon.bottou.org/projects/infimnist) |
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### MATLAB Loading Example |
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``` |
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dataset_name = 'MNIST8M'; |
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% Data path |
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data_file = 'MNIST8M_data.h5'; % Your directory |
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data = h5read(data_file, '/MNIST8M'); |
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data = double(data); % May cause out-of-memory |
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data_info = h5info(data_file); |
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data_size = data_info.Datasets.Dataspace.Size; |
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n_points = data_size(1); % Total number of points |
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n_features = data_size(2); % Number of dimensions |
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``` |
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``` |
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>> h5disp('MNIST8M_data.h5'); |
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HDF5 MNIST8M_data.h5 |
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Group '/' |
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Dataset 'MNIST8M' |
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Size: 8100000x784 |
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MaxSize: 8100000x784 |
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Datatype: H5T_STD_U8LE (uint8) |
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ChunkSize: 100000x784 |
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Filters: none |
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FillValue: 0 |
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``` |
