How do I generate a sinusoidal waveform for frequency 0,05Hz?

Hi everyone,
I generate a sinusoidal waveform for different amplitude and frequencies. However, I can not obtain a waveform for frequency<0,05 Hz. For the frequency values under freq=0,05 Hz, the vi gives an error as can be seen from the attachment picture. I have changed the "buffer size", "scan rate", "total scan to acquire" and "count", but it failed again and gave the same error. Is there anyone who can deal with or experienced with something like this problem? Also, could you please the exact meaning of
scan rate=
total scan to acquire=
buffer size=
In order to prevent the aliasing, what should be these values? What kind of relations are there between them? Because, for different selected frequencies, I have to change these values, otherwise I detect wrong frequency value using "Tone Measurements.vi" that is located at the LabView library.
Also, could you please make a comment on filtering? I want to filter very small vibrations from the signal using express vi of "Filter.vi". Should I have to use lowpass filter, or highpass filter, or bandpass or, smoothing etc. and what value of "cuttoff frequency" should I use? Thanks a lot...
Attachments:
front.jpg ‏333 KB
Unsteady Pipe Flow Analysis.zip ‏126 KB

Hi,
I have also attached two files. One is related with f=1 Hz. When I adjust the frequency to 1 Hz, I can obtain and detect the true frequency response. However, as can be seen the waveform graph in the 1 Hz.jpg, I do not want to save or analyse the data which I circled in green colour. Because, the hotwire begins from the zero value and there is a peak at the top.After the first period, the waveform comes through the periodic one. Start of period from zero and make a bit peak at the top will change my statistic analysisi of signal. So I want to omit the first period.
In the second attachement, (f=10Hz.jpg), ı changed the frequency of the signal from 1 Hz to 10 Hz. Now, the vi detected the wrong frequency as can be seen from the picture "Detected Frequency=0,1". Also, the waveform graph does not show the right periodic signal.
So, what is the wrong? The filtering? or the scan rate? , total scan to acquire?, buffer size????? or what?? I have tried many different combinations of these control values, but the vi always detected the wrong frequency and the waveform graph was always like that.
Attachments:
f=1 Hz.jpg ‏307 KB
f=10Hz.jpg ‏311 KB

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How do I generate a sinusoidal waveform for frequency 0,05Hz?

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