Zero phase filtering initial condition effect

Hi
I was wondering if any body knows how I can handle the problem of edge effect caused by zero phase filtering? The problem is that by using zero phase filtering if the intial condition of forward filter does not equal to that of reverse filter, a kind of spike will occur at the begining and the end of filtered signal. In MATLAB spacial care has been taken to minimize this effect but it seems it is not the case in LabView?
I noticed that some body mentioned the same problem here long time ago and one of replies pointed out that it is the transient effect of convolution and we need to remove the first and last samples of filtered signal but I don't think that it is a wise solution because the problem is not because of convolution.
Best regards
Afshin

The math is correct, but you can not compare directly to the math used then dealing with continuous math functions like sin(x). Use scaling functions to if you want to "correct" the amplitude. Do not change the dt value
Besides which, my opinion is that Express VIs Carthage must be destroyed deleted
(Sorry no Labview "brag list" so far)
Attachments:
Derivative[1].vi ‏19 KB

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Is it possible to use Zero phase filter for continuous filtering?

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AJ_CS wrote:
The zero phase filtering method seen in your thread will work, if the filtering happens as a single shot operation. It will remove the edge effects of zero phase filtering.
But for an application wherein data arrives as small blocks, it has to filter each block of the data and also it has to maintain the continuity of filtering.
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