python/examlpes.py

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# to you under the Apache License, Version 2.0 (the
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#
#     http://www.apache.org/licenses/LICENSE-2.0
#
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# specific language governing permissions and limitations
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#

import numpy as np
import pandas as pd
import os

import tsfile as ts


# test writing data
data_dir = os.path.join(os.path.dirname(__file__), "test.tsfile")
DEVICE_NAME = "test_table"

# 1000 rows data
time = np.arange(1, 1001, dtype=np.int64)
level = np.linspace(2000, 3000, num=1000, dtype=np.float32)
num = np.arange(10000, 11000, dtype=np.int64)
df = pd.DataFrame({"Time": time, "level": level, "num": num})

if os.path.exists(data_dir):
    os.remove(data_dir)
ts.write_tsfile(data_dir, DEVICE_NAME, df)


# read data we already wrote
# with 20 chunksize
tsfile_ret = ts.read_tsfile(data_dir, DEVICE_NAME, ["level", "num"], chunksize=20)
print(tsfile_ret.shape)

# with 100 chunksize
tsfile_ret = ts.read_tsfile(data_dir, DEVICE_NAME, ["level", "num"], chunksize=100)
print(tsfile_ret.shape)

# get all data
tsfile_ret = ts.read_tsfile(data_dir, DEVICE_NAME, ["level", "num"])
print(tsfile_ret.shape)

# with iterator
with ts.read_tsfile(
    data_dir, DEVICE_NAME, ["level", "num"], iterator=True, chunksize=100
) as reader:
    for chunk in reader:
        print(chunk.shape)

# with time scale and chunksize
tsfile_ret = ts.read_tsfile(
    data_dir, DEVICE_NAME, ["level"], start_time=50, end_time=100, chunksize=10
)
print(tsfile_ret.shape)

# with time scale
tsfile_ret = ts.read_tsfile(data_dir, DEVICE_NAME, ["num"], start_time=50, end_time=100)
print(tsfile_ret.shape)

# with time scale, iterator and chunksize
with ts.read_tsfile(
    data_dir,
    DEVICE_NAME,
    ["level", "num"],
    iterator=True,
    start_time=100,
    end_time=500,
    chunksize=100,
) as reader:
    for chunk in reader:
        print(chunk.shape)