Recent content by cutesteph

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    DSP Tuner - Is this correct for freq offset?

    Say I already calculated the frequency offset after the ADC, which was calculated using a 1,048,576 FFT, but I only have 1,040,000 IQ samples. Do I need to use a non power of two FFT method or will the follow work? freq corrected IQdata = sum of iqData(i)*[exp(i*2*pi* n*freq_offset*(diff...
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    How many hadamard matrix matrices exists for size n?

    Homework Statement How many hadamard matrices exists for size n? Homework Equations Hadamard matrices are square matrices whose entries are either +1 or −1 and whose rows are mutually orthogonal. The Attempt at a Solution I am just curious how many exists for 4, 8 and in general.[/B]
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    Multiple linear regression

    Or should it be appropriate to use reading score since it has the best correlation and least spread even though test scores is the average of reading score and math score.
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    Multiple linear regression

    I am doing a multiple linear regression on a dataset. It is test scores. It has three highly correlated variables being income, reading score, and math score. Obviously since the test score is the sum of the math score and reading score would it be appropriate to exclude them simply based off...
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    PCA principal component analysis standardized data

    Yes. It would be which would be equivalent to using the correlation matrix in lieu of the covariance matrix for PCA. I just not sure exactly why would it be better to use that method than to just chance the units to the same units of say in my example meters per second for each different race...
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    PCA principal component analysis standardized data

    I mean like say we are looking are car race data like from 1/4 a mile 1 mile are in seconds, while data for a 10 mile and a 50 mile race are in minutes. Can't you use normalize data using the correlation matrix within each group like 1/4 mile race even though it is in seconds to a 10 mile race...
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    PCA principal component analysis standardized data

    Why is better to use the standardized data using the correlation matrix than say converting data into just similar units. Like say I had data that measured car speeds measured in seconds for some data and the other data measured in minutes. Why would it be better just to measure the data using...
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    How Does the GET_UINT32 Macro Convert Input into Hexadecimal Format?

    Homework Statement this is in my function GET_UINT32( X, input, 0 ); this is a macro #define GET_UINT32(n,b,i) \ { \ (n) = ( (uint32) (b)[(i) ] << 24 ) \ | ( (uint32) (b)[(i) + 1] << 16 ) \ | ( (uint32) (b)[(i) + 2] << 8 ) \ | ( (uint32) (b)[(i) + 3] ); \ } 3435973836=0xcccccccc when inputted...
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    First time a^d = 1 mod n

    d is to be found. Essentially I want to find the smallest integer d such that a^d = 1 mod n holds true. Yes, For any positive integer a and n, find the first integer d such that a^d =1 mod n is how the problem should have been stated.
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    First time a^d = 1 mod n

    Homework Statement For any positive integer d and n, find the first integer d such that a^d =1 mod n Homework Equations Euler's totient function phi(n) = # of #s relatively prime to n Will solve the condition if a and n are coprime but not for the first d The Attempt at a Solution If a and n...
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    Least squares of a constant

    Suppose we have an observation y = c+ e where c is an unknown constant and e is error with the pdf = exp(-e-1) for e >-1 . We want to determine the least square estimator of c given by the c* which minimizes the error cost function E(c) = .5(y-c)^2 Minimizing the error cost is done by taking...
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    Calculus - Minimizing functions

    Basically I am finding the maximum likelihood estimator x which is equivalent to maximizing the function exp(-y+x-1) where y >= x-1 . e is representing error and distributed exponentially with parameter L means that it follows a distribution L*exp(-L*x).
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    Calculus - Minimizing functions

    Homework Statement Maximize the function for x. exp(-y+x-1) for y >= x-1 and y=x+e where e is distributed exp(L) The Attempt at a Solution d/dx(ln(exp(-y+x-1)) = 0 => d/dx(-y+x-1) = 0 but if I take the derivative of this x goes away.
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    Maximum Likelihood Estimation for Constant x and Exponential Distribution of z

    Homework Statement y=x+z where the pdf of z is exp(-v-2) for v >= 2 and 0 otherwise and x is just an unknown constant what is the MLE of z which maximizes the condition density f_v(y-x)Homework Equations The Attempt at a Solution f_v(y-x) = integral of -2+x to infinity of exp(-y+x-2) dy =...
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    Similar Matrices: Showing A Not Similar to B

    Homework Statement A=[a,1;0,a] B=[a,0;0,a] If I want to show if matrix A is NOT similar to matrix B. Is it enough to show that B=/=Inv(P)*A*P? Or would I need to show that they do not have both the same eigenvalues and corresponding eigenvectors?
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