Add and update AI examples. (#566)

* added and updated AI examples

* reworked as per given comments

* fixed style error

* added pprint in event example

* reworked and file renamed as per suggestions

* remind user before start task in event example

* reduced samples per chan

* reduced samples per chan for event example

* print total read in cont examples

* removed samps_per_chan for cont examples

* added :f for single read examples

examples/analog_in/cont_voltage_acq_int_clk.py

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+"""Example of analog input voltage acquisition.
+
+This example demonstrates how to acquire a continuous amount of data
+using the DAQ device's internal clock.
+"""
+
+import nidaqmx
+from nidaqmx.constants import AcquisitionType
+
+with nidaqmx.Task() as task:
+    task.ai_channels.add_ai_voltage_chan("Dev1/ai0")
+    task.timing.cfg_samp_clk_timing(1000.0, sample_mode=AcquisitionType.CONTINUOUS)
+    task.start()
+    print("Running task. Press Ctrl+C to stop.")
+
+    try:
+        total_read = 0
+        while True:
+            data = task.read(number_of_samples_per_channel=1000)
+            read = len(data)
+            total_read += read
+            print(f"Acquired data: {read} samples. Total {total_read}.", end="\r")
+    except KeyboardInterrupt:
+        pass
+    finally:
+        task.stop()
+        print(f"\nAcquired {total_read} total samples.")

examples/analog_in/cont_voltage_acq_int_clk_every_n_samples_event.py

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+"""Example of analog input voltage acquisition with events.
+
+This example demonstrates how to use Every N Samples events to
+acquire a continuous amount of data using the DAQ device's
+internal clock. The Every N Samples events indicate when data is
+available from DAQmx.
+"""
+
+import nidaqmx
+from nidaqmx.constants import AcquisitionType
+
+
+def main():
+    """Continuously acquires data using an Every N Samples event."""
+    total_read = 0
+    with nidaqmx.Task() as task:
+
+        def callback(task_handle, every_n_samples_event_type, number_of_samples, callback_data):
+            """Callback function for reading singals."""
+            nonlocal total_read
+            read = len(task.read(number_of_samples_per_channel=number_of_samples))
+            total_read += read
+            print(f"Acquired data: {read} samples. Total {total_read}.", end="\r")
+
+            return 0
+
+        task.ai_channels.add_ai_voltage_chan("Dev1/ai0")
+        task.timing.cfg_samp_clk_timing(1000.0, sample_mode=AcquisitionType.CONTINUOUS)
+        task.register_every_n_samples_acquired_into_buffer_event(1000, callback)
+        task.start()
+
+        input("Running task. Press Enter to stop.\n")
+
+        task.stop()
+        print(f"\nAcquired {total_read} total samples.")
+
+
+if __name__ == "__main__":
+    main()

examples/analog_in/thrmcpl_sample.py

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+"""Example of analog input temperature acquisition.
+
+This example demonstrates how to acquire thermocouple measurement using
+software timing.
+"""
+
+import nidaqmx
+from nidaqmx.constants import ThermocoupleType, TemperatureUnits
+
+with nidaqmx.Task() as task:
+    task.ai_channels.add_ai_thrmcpl_chan(
+        "Dev1/ai0", units=TemperatureUnits.DEG_C, thermocouple_type=ThermocoupleType.K
+    )
+
+    data = task.read()
+    print(f"Acquired data: {data:f}")

examples/analog_in/voltage_acq_int_clk.py

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+"""Example of analog input voltage acquisition.
+
+This example demonstrates how to acquire a finite amount
+of data using the DAQ device's internal clock.
+"""
+
+import nidaqmx
+from nidaqmx.constants import AcquisitionType, READ_ALL_AVAILABLE
+
+with nidaqmx.Task() as task:
+    task.ai_channels.add_ai_voltage_chan("Dev1/ai0")
+    task.timing.cfg_samp_clk_timing(1000.0, sample_mode=AcquisitionType.FINITE, samps_per_chan=50)
+
+    data = task.read(READ_ALL_AVAILABLE)
+    print("Acquired data: [" + ", ".join(f"{value:f}" for value in data) + "]")

examples/analog_in/voltage_sample.py

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+"""Example of analog input voltage acquisition.
+
+This example demonstrates how to acquire a voltage measurement using software timing.
+"""
+
+import nidaqmx
+
+with nidaqmx.Task() as task:
+    task.ai_channels.add_ai_voltage_chan("Dev1/ai0")
+
+    data = task.read()
+    print(f"Acquired data: {data:f}")