MathScript fir1 function vs. LabVIEW FIR VI

Hi, I'd like to convert some Matlab/LabVIEW Mathscript function into LabVIEW block functions, because it's faster.
One
of the function I'm not sure is the FIR function: I have a Mathscrip
function fir1(n,W), is "FIR windowed coefficients" its LabVIEW
equivalent? If yes, how should I match the parameters (e.g. is W the
high or low curoff frequency? is Order n the same as the number of
taps)? If no, which LabVIEW function should I use?
Thanks.

Hi,
The corresponding VI in LabVIEW is FIR Windowed Coefficients VI. For the simple case b = fir1(n, w), you can use the way as the attached snapshot illustrates.
Attachments:
fir1.PNG ‏7 KB

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How to create a filter using mathscript transfer function in labview

Dear all,
I am currently designing a filter in labview using a Mathscript looping. The filter can be represented in transfer function. I have attachted the transfer function equation together with its value and the desire frequency vs. amplitude graph that I should obtained from it. Also, following are the transfer function written in Matlab.
B1= tf ([57.5221845],[1 51.017077 205.1868]);
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Hope to have the soonest reply from you guys. Many thanks in advance
Solved!
Go to Solution.
Attachments:
transfer function.jpg ‏18 KB
Weighting Filter.vi ‏266 KB

Thank you again for offering to help me in writing the code.
I suppose that I should do a frequency sweep on the transfer
function to prove that it behave as the sample graph. Example, if I have an input sine
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and of cause the frequency range of my input sine wave would only be between
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Attachments:
Weighting FilterTest1.vi ‏53 KB

Mathscript/Matlab fir1 function vs. LabVIEW FIR coefficient?

I'd like to convert some Matlab/LabVIEW Mathscript function into LabVIEW block functions, because it's faster.
One of the function I'm not sure is the FIR function: I have a Mathscrip function fir1(n,W), is "FIR windowed coefficients" its LabVIEW equivalent? If yes, how should I match the parameters (e.g. is W the high or low curoff frequency? is Order n the same as the number of taps)? If no, which LabVIEW function should I use?
Thanks.

Hi pji,
I don't have LabVIEW, but I found some really useful resources in LabVIEW Help (open labVIEW>>Help>>search the LabVIEW Help>>search)
Search for fir1 and it contains the syntax, paramter definition and some example codes which you can simply copy and paste and run
b = fir1(n, w)
n: Specifies the filter order. n is a nonnegative integer.
n must be even for filters with a non-zero gain at the Nyquist
frequency. If n does not meet this condition, LabVIEW increases
n by 1.
w: Specifies the cutoff frequency of the filter. w is real number
between 0 and 1. 1 represents the Nyquist frequency.LabVIEW Help has abundant information, check it out!!!
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MIDI Read function in LabVIEW 8.2

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http://forums.ni.com/ni/board/message?board.id=170&message.id=280480#M280480
You could have aksed it in your previous post since it concerns the same functions.
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On Sat, 10 Jul 1999 23:19:29 GMT, Greg McKaskle
wrote:
>> I've got a question concerning functions in Labview.
>> Is it possible to see the *source* of a function ?
>> I'm working with the "Butterworth filter" and I need to know how it
>> works *in the inside* :]
>>
>
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>
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Solved!
Go to Solution.
Attachments:
libfli-32.zip ‏93 KB

Hi, Smercurio_fc
thanks for your reply. Yes, you are pointing to the right place. I have solved the crash problem.
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as for the size_t,
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add additional include path as
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for this case I know that the DLL is built from VC++, is this right way?
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xiaofeng
Attachments:
test.vi ‏13 KB

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MathScript fir1 function vs. LabVIEW FIR VI

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