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45 lines
1.0 KiB
Python
45 lines
1.0 KiB
Python
# Different methods to read from text files
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# sr 11/18/2013
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# Python 3.x
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# Note: rb opens file in binary mode to avoid issues with Windows systems
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# where '\r\n' is used instead of '\n' as newline character(s).
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# A) Reading in Byte chunks
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reader_a = open("file.txt", "rb")
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chunks = []
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data = reader_a.read(64) # reads first 64 bytes
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while data != "":
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chunks.append(data)
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data = reader_a.read(64)
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if data:
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chunks.append(data)
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print (len(chunks))
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reader_a.close()
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# B) Reading whole file at once into a list of lines
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with open("file.txt", "rb") as reader_b: # recommended syntax, auto closes
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data = reader_b.readlines() # data is assigned a list of lines
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print (len(data))
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# C) Reading whole file at once into a string
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with open("file.txt", "rb") as reader_c:
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data = reader_c.read() # data is assigned a list of lines
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print (len(data))
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# D) Reading line by line into a list
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data = []
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with open("file.txt", "rb") as reader_d:
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for line in reader_d:
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data.append(line)
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print (len(data))
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