mirror of
https://github.com/wassname/segpy.git
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Robert Smallshire
52 lines
1.1 KiB
Python
52 lines
1.1 KiB
Python
"""Mappings between the coding systems used for sample types.
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"""
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# A mapping from data sample format codes to SEG Y types.
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DATA_SAMPLE_FORMAT_TO_SEG_Y_TYPE = {
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1: 'ibm',
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2: 'int32',
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3: 'int16',
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5: 'float32',
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8: 'int8'}
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# A mapping from SEG Y data types to format characters used by the
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# Python Standard Library struct module
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SEG_Y_TYPE_TO_CTYPE = {
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'int32': 'i',
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'uint32': 'I',
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'int16': 'h',
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'uint16': 'H',
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'int8': 'b',
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'uint8': 'B',
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'float32': 'f',
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'ibm': 'ibm'}
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# Human readable descriptions of the sample types.
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SEG_Y_TYPE_DESCRIPTION = {
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'ibm': 'IBM 32 bit float',
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'int32': '32 bit signed integer',
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'uint32': '32 bit unsigned integer',
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'int16': '16 bit signed integer',
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'uint16': '16 bit unsigned integer',
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'float32': 'IEEE float32',
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'int8': '8 bit signed integer (byte)',
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'uint8': '8 bit unsigned integer (byte)'}
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# Sizes of various ctypes in bytes
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CTYPE_TO_SIZE = dict(
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i=4,
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I=4,
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h=2,
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H=2,
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b=1,
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B=1,
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f=4,
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ibm=4)
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def size_in_bytes(ctype):
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"""The size in bytes of a ctype.
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"""
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return CTYPE_TO_SIZE[ctype]
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