Python - Python Misc, os, shutil

sys

• Check current python version

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if sys.version_info.major == 3 and sys.version_info.minor == 10:
    print("Python version is 3.10")
else:
    print(f"Python version is not 3.10, it's {sys.version_info.major}.{sys.version_info.minor}")

Numbers

• Not a number float('nan'). This is often seen in 0/0
  • In numpy, this is np.nan. To check, it’s numpy.isnan()

Print Options

• Multiline Printing

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print(f'''
line 1
line2
''')

• Print float with 2 decimal digits

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print(f"{test_acc:.2f}%")

Argparse

• Adding a required arg:

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parser.add_argument("--name", "-n", type=str, required=True, help="Name of a bag in rgbd_slam_rico/data")

Path Related

os Library

• Absolute Path

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script_path = os.path.abspath(__file__)

• Remove a file if it exists:

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if os.path.exists(output_path):
    os.remove(output_path)

shutil

• remove non-empty directory:

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shutil.rmtree(DIR)

For-Else Loop

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k = 10
for i in range(k):
    print(k)
    break
else:
    print("hello")

HDF5

• open-source file for store large amount of data
  • largely used in numpy community
  • Can handle many different datatypes in multiple data blocks, with metadata
  • We can access them in data blocks
  • numpy array holds the data, and directly to and from the data.
  • used as ML model weights
• To use HDF5, numpy needs to be imported.

Formatting

isort will reorder this. But you can turn off the formatting for now so path is properly added

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# fmt: off
sys.path.insert(0, os.path.join(os.path.dirname(os.path.abspath(__file__)), "..", "models", "Chamfer3D"))
from dist_chamfer_3D import chamfer_3DDist, chamfer_3DFunction
# fmt: on

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