uproot.compression.compress
Defined in uproot.compression on line 524.
- uproot.compression.compress(data: bytes, compression: Compression) bytes
- Parameters:
- data (bytes, memoryview, or NumPy array) – Data to compress. 
- compression (uproot.compression.Compression) – Algorithm and level to use in compressing the data. 
 
 - Compress - datausing- compressionand return a bytes object (or the original object in some circumstances).- This function generates ROOT’s 9-byte compression headers (17 bytes for LZ4 because it includes a checksum), with multiple blocks for each 2**24 - 1 bytes of input. The return value has all blocks concatenated into a single bytes object, and the splitting into multiple blocks is necessary because the compression headers can only specify uncompressed and compressed sizes up to 2**24 - 1. - If the compression level ( - compression.level) is zero or the compressed output would be larger than the input, the input is returned instead, in whatever format (bytes, memoryview, or NumPy array) it was provided.