Read and write npy files.

This commit is contained in:
laurent
2023-06-24 18:12:10 +01:00
parent a6ca9baf3c
commit a7f80e258f
5 changed files with 410 additions and 1 deletions

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@ -21,6 +21,7 @@ thiserror = "1"
cudarc = { version = "0.9.9", optional = true }
candle-kernels = { path = "kernels", optional = true }
gemm = "0.15.4"
zip = "0.6.6"
[dev-dependencies]
anyhow = "1"

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@ -1,7 +1,9 @@
#![allow(dead_code)]
use crate::{CpuStorage, DType, Error, Result, Shape};
pub type CudaError = std::io::Error;
#[derive(thiserror::Error, Debug)]
pub enum DummyError {}
pub type CudaError = DummyError;
#[derive(Debug, Clone)]
pub struct CudaDevice;

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@ -75,6 +75,21 @@ pub enum Error {
#[error(transparent)]
TryFromIntError(#[from] core::num::TryFromIntError),
#[error("npy/npz error {0}")]
Npy(String),
/// Zip file format error.
#[error(transparent)]
Zip(#[from] zip::result::ZipError),
/// Integer parse error.
#[error(transparent)]
ParseInt(#[from] std::num::ParseIntError),
/// I/O error.
#[error(transparent)]
Io(#[from] std::io::Error),
}
pub type Result<T> = std::result::Result<T, Error>;

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@ -5,6 +5,7 @@ mod device;
mod dtype;
mod dummy_cuda_backend;
mod error;
mod npy;
mod op;
mod shape;
mod storage;

390
src/npy.rs Normal file
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@ -0,0 +1,390 @@
//! Numpy support for literals.
//!
//! The spec for the npy format can be found in
//! [npy-format](https://docs.scipy.org/doc/numpy-1.14.2/neps/npy-format.html).
//! The functions from this module can be used to read literals from npy/npz files
//! or write literals to these files. A npy file contains a single literal (unnamed)
//! whereas a npz file can contain multiple named literals. npz files are also compressed.
//!
//! These two formats are easy to use in Python using the numpy library.
//!
//! ```python
//! import numpy as np
//! x = np.arange(10)
//!
//! # Write a npy file.
//! np.save("test.npy", x)
//!
//! # Read a value from the npy file.
//! x = np.load("test.npy")
//!
//! # Write multiple values to a npz file.
//! values = { "x": x, "x_plus_one": x + 1 }
//! np.savez("test.npz", **values)
//!
//! # Load multiple values from a npz file.
//! values = np.loadz("test.npz")
//! ```
use crate::{DType, Device, Error, Result, Shape, Tensor};
use std::collections::HashMap;
use std::fs::File;
use std::io::{BufReader, Read, Write};
use std::path::Path;
const NPY_MAGIC_STRING: &[u8] = b"\x93NUMPY";
const NPY_SUFFIX: &str = ".npy";
fn read_header<R: Read>(reader: &mut R) -> Result<String> {
let mut magic_string = vec![0u8; NPY_MAGIC_STRING.len()];
reader.read_exact(&mut magic_string)?;
if magic_string != NPY_MAGIC_STRING {
return Err(Error::Npy("magic string mismatch".to_string()));
}
let mut version = [0u8; 2];
reader.read_exact(&mut version)?;
let header_len_len = match version[0] {
1 => 2,
2 => 4,
otherwise => return Err(Error::Npy(format!("unsupported version {otherwise}"))),
};
let mut header_len = vec![0u8; header_len_len];
reader.read_exact(&mut header_len)?;
let header_len = header_len
.iter()
.rev()
.fold(0_usize, |acc, &v| 256 * acc + v as usize);
let mut header = vec![0u8; header_len];
reader.read_exact(&mut header)?;
Ok(String::from_utf8_lossy(&header).to_string())
}
#[derive(Debug, PartialEq)]
struct Header {
descr: DType,
fortran_order: bool,
shape: Vec<usize>,
}
impl Header {
fn shape(&self) -> Shape {
Shape::from(self.shape.as_slice())
}
fn to_string(&self) -> Result<String> {
let fortran_order = if self.fortran_order { "True" } else { "False" };
let mut shape = self
.shape
.iter()
.map(|x| x.to_string())
.collect::<Vec<_>>()
.join(",");
let descr = match self.descr {
DType::F32 => "f4",
DType::F64 => "f8",
DType::U32 => "u4",
};
if !shape.is_empty() {
shape.push(',')
}
Ok(format!(
"{{'descr': '<{descr}', 'fortran_order': {fortran_order}, 'shape': ({shape}), }}"
))
}
// Hacky parser for the npy header, a typical example would be:
// {'descr': '<f8', 'fortran_order': False, 'shape': (128,), }
fn parse(header: &str) -> Result<Header> {
let header =
header.trim_matches(|c: char| c == '{' || c == '}' || c == ',' || c.is_whitespace());
let mut parts: Vec<String> = vec![];
let mut start_index = 0usize;
let mut cnt_parenthesis = 0i64;
for (index, c) in header.chars().enumerate() {
match c {
'(' => cnt_parenthesis += 1,
')' => cnt_parenthesis -= 1,
',' => {
if cnt_parenthesis == 0 {
parts.push(header[start_index..index].to_owned());
start_index = index + 1;
}
}
_ => {}
}
}
parts.push(header[start_index..].to_owned());
let mut part_map: HashMap<String, String> = HashMap::new();
for part in parts.iter() {
let part = part.trim();
if !part.is_empty() {
match part.split(':').collect::<Vec<_>>().as_slice() {
[key, value] => {
let key = key.trim_matches(|c: char| c == '\'' || c.is_whitespace());
let value = value.trim_matches(|c: char| c == '\'' || c.is_whitespace());
let _ = part_map.insert(key.to_owned(), value.to_owned());
}
_ => return Err(Error::Npy(format!("unable to parse header {header}"))),
}
}
}
let fortran_order = match part_map.get("fortran_order") {
None => false,
Some(fortran_order) => match fortran_order.as_ref() {
"False" => false,
"True" => true,
_ => return Err(Error::Npy(format!("unknown fortran_order {fortran_order}"))),
},
};
let descr = match part_map.get("descr") {
None => return Err(Error::Npy("no descr in header".to_string())),
Some(descr) => {
if descr.is_empty() {
return Err(Error::Npy("empty descr".to_string()));
}
if descr.starts_with('>') {
return Err(Error::Npy(format!("little-endian descr {descr}")));
}
// the only supported types in tensor are:
// float64, float32, float16,
// complex64, complex128,
// int64, int32, int16, int8,
// uint8, and bool.
match descr.trim_matches(|c: char| c == '=' || c == '<' || c == '|') {
// "e" | "f2" => DType::F16,
"f" | "f4" => DType::F32,
"d" | "f8" => DType::F64,
// "i" | "i4" => DType::S32,
// "q" | "i8" => DType::S64,
// "h" | "i2" => DType::S16,
// "b" | "i1" => DType::S8,
// "B" | "u1" => DType::U8,
"I" | "u4" => DType::U32,
// "?" | "b1" => DType::Pred,
// "F" | "F4" => DType::C64,
// "D" | "F8" => DType::C128,
descr => return Err(Error::Npy(format!("unrecognized descr {descr}"))),
}
}
};
let shape = match part_map.get("shape") {
None => return Err(Error::Npy("no shape in header".to_string())),
Some(shape) => {
let shape = shape.trim_matches(|c: char| c == '(' || c == ')' || c == ',');
if shape.is_empty() {
vec![]
} else {
shape
.split(',')
.map(|v| v.trim().parse::<usize>())
.collect::<std::result::Result<Vec<_>, _>>()?
}
}
};
Ok(Header {
descr,
fortran_order,
shape,
})
}
}
impl Tensor {
fn from_reader<R: std::io::Read>(shape: Shape, dtype: DType, reader: &mut R) -> Result<Self> {
let elem_count = shape.elem_count();
match dtype {
DType::F32 => {
let mut data = Vec::new();
data.reserve(elem_count);
for _ in 0..elem_count {
let mut buf = [0u8; 4];
reader.read_exact(&mut buf)?;
data.push(f32::from_le_bytes(buf))
}
// TODO: We should pass the ownership of data here rather than triggering a copy.
Tensor::from_slice(&data, shape, &Device::Cpu)
}
DType::F64 => {
let mut data = Vec::new();
data.reserve(elem_count);
for _ in 0..elem_count {
let mut buf = [0u8; 8];
reader.read_exact(&mut buf)?;
data.push(f64::from_le_bytes(buf))
}
Tensor::from_slice(&data, shape, &Device::Cpu)
}
DType::U32 => {
let mut data = Vec::new();
data.reserve(elem_count);
for _ in 0..elem_count {
let mut buf = [0u8; 4];
reader.read_exact(&mut buf)?;
data.push(u32::from_le_bytes(buf))
}
Tensor::from_slice(&data, shape, &Device::Cpu)
}
}
}
/// Reads a npy file and return the stored multi-dimensional array as a literal.
pub fn read_npy<T: AsRef<Path>>(path: T) -> Result<Self> {
let mut reader = File::open(path.as_ref())?;
let header = read_header(&mut reader)?;
let header = Header::parse(&header)?;
if header.fortran_order {
return Err(Error::Npy("fortran order not supported".to_string()));
}
let mut data: Vec<u8> = vec![];
reader.read_to_end(&mut data)?;
Self::from_reader(header.shape(), header.descr, &mut reader)
}
/// Reads a npz file and returns the stored multi-dimensional arrays together with their names.
pub fn read_npz<T: AsRef<Path>>(path: T) -> Result<Vec<(String, Self)>> {
let zip_reader = BufReader::new(File::open(path.as_ref())?);
let mut zip = zip::ZipArchive::new(zip_reader)?;
let mut result = vec![];
for i in 0..zip.len() {
let mut reader = zip.by_index(i).unwrap();
let name = {
let name = reader.name();
name.strip_suffix(NPY_SUFFIX).unwrap_or(name).to_owned()
};
let header = read_header(&mut reader)?;
let header = Header::parse(&header)?;
if header.fortran_order {
return Err(Error::Npy("fortran order not supported".to_string()));
}
let s = Self::from_reader(header.shape(), header.descr, &mut reader)?;
result.push((name, s))
}
Ok(result)
}
/// Reads a npz file and returns the stored multi-dimensional arrays for some specified names.
pub fn read_npz_by_name<T: AsRef<Path>>(path: T, names: &[&str]) -> Result<Vec<Self>> {
let zip_reader = BufReader::new(File::open(path.as_ref())?);
let mut zip = zip::ZipArchive::new(zip_reader)?;
let mut result = vec![];
for name in names.iter() {
let mut reader = match zip.by_name(&format!("{name}{NPY_SUFFIX}")) {
Ok(reader) => reader,
Err(_) => Err(Error::Npy(format!(
"no array for {name} in {:?}",
path.as_ref()
)))?,
};
let header = read_header(&mut reader)?;
let header = Header::parse(&header)?;
if header.fortran_order {
return Err(Error::Npy("fortran order not supported".to_string()));
}
let s = Self::from_reader(header.shape(), header.descr, &mut reader)?;
result.push(s)
}
Ok(result)
}
fn write<T: Write>(&self, f: &mut T) -> Result<()> {
f.write_all(NPY_MAGIC_STRING)?;
f.write_all(&[1u8, 0u8])?;
let header = Header {
descr: self.dtype(),
fortran_order: false,
shape: self.dims().to_vec(),
};
let mut header = header.to_string()?;
let pad = 16 - (NPY_MAGIC_STRING.len() + 5 + header.len()) % 16;
for _ in 0..pad % 16 {
header.push(' ')
}
header.push('\n');
f.write_all(&[(header.len() % 256) as u8, (header.len() / 256) as u8])?;
f.write_all(header.as_bytes())?;
let elem_count = self.elem_count();
match self.dtype() {
DType::F32 => {
// TODO: Avoid using a buffer when data is already on the CPU.
for v in self.reshape(elem_count)?.to_vec1::<f32>()? {
f.write_all(&v.to_le_bytes())?;
}
}
DType::F64 => {
for v in self.reshape(elem_count)?.to_vec1::<f64>()? {
f.write_all(&v.to_le_bytes())?;
}
}
DType::U32 => {
for v in self.reshape(elem_count)?.to_vec1::<u32>()? {
f.write_all(&v.to_le_bytes())?;
}
}
}
Ok(())
}
/// Writes a multi-dimensional array in the npy format.
pub fn write_npy<T: AsRef<Path>>(&self, path: T) -> Result<()> {
let mut f = File::create(path.as_ref())?;
self.write(&mut f)
}
/// Writes multiple multi-dimensional arrays using the npz format.
pub fn write_npz<S: AsRef<str>, T: AsRef<Tensor>, P: AsRef<Path>>(
ts: &[(S, T)],
path: P,
) -> Result<()> {
let mut zip = zip::ZipWriter::new(File::create(path.as_ref())?);
let options =
zip::write::FileOptions::default().compression_method(zip::CompressionMethod::Stored);
for (name, tensor) in ts.iter() {
zip.start_file(format!("{}.npy", name.as_ref()), options)?;
tensor.as_ref().write(&mut zip)?
}
Ok(())
}
}
#[cfg(test)]
mod tests {
use super::Header;
#[test]
fn parse() {
let h = "{'descr': '<f8', 'fortran_order': False, 'shape': (128,), }";
assert_eq!(
Header::parse(h).unwrap(),
Header {
descr: crate::DType::F64,
fortran_order: false,
shape: vec![128]
}
);
let h = "{'descr': '<f4', 'fortran_order': True, 'shape': (256,1,128), }";
let h = Header::parse(h).unwrap();
assert_eq!(
h,
Header {
descr: crate::DType::F32,
fortran_order: true,
shape: vec![256, 1, 128]
}
);
assert_eq!(
h.to_string().unwrap(),
"{'descr': '<f4', 'fortran_order': True, 'shape': (256,1,128,), }"
);
let h = Header {
descr: crate::DType::U32,
fortran_order: false,
shape: vec![],
};
assert_eq!(
h.to_string().unwrap(),
"{'descr': '<u4', 'fortran_order': False, 'shape': (), }"
);
}
}