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Error message using 'double' ?

  1. Feb 16, 2012 #1
    Error message using 'double' ??

    I'm writing a function with the algorithm to compute the QR factorization of the matrix A, when I go to use my function and input a matrix A I get the error message

    Undefined function or method 'qrfac' for input arguments of type 'double'

    and I have no clue what I'm doing wrong. Help please!

  2. jcsd
  3. Feb 16, 2012 #2


    Staff: Mentor

    Re: Error message using 'double' ??

    You haven't provided much information, but from the error message, you are probably not providing the right types of arguments to qrfac. Look at the documentation for qrfac, and make sure that the arguments in your call to qrfac are the same types as it expects.

    Is this fortran code you're writing?
  4. Jun 22, 2012 #3
    Re: Error message using 'double' ??

    I have identical problem on MATLAB 7.10.0 (R2010a):

    Q =

    0.4472 0 0 0 0
    0.4472 1.0000 0 0 0
    0.4472 0 1.0000 0 0
    0.4472 0 0 1.0000 0
    0.4472 0 0 0 1.0000

    ??? Undefined function or method 'QR' for input arguments of type 'double'.

    any clue?
  5. Jun 22, 2012 #4

    D H

    User Avatar
    Staff Emeritus
    Science Advisor

    Re: Error message using 'double' ??

    Use qr(Q) rather than QR(Q). Matlab's built-in function names are case sensitive.
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