Troubles with zerocrossings

Submitted by petterwr on Fri, 10/28/2011 - 11:11

I've been trying to find the zerocrossings for some of my data. It all works well when I do the examples but when i use my own data it turns out like this:

 

-->accy=fulltable(7,21:30)
accy  =

        column 1 to 6

! 2.9037828   4.237953   4.473395   4.0025115   0.23544185   -3.2177052  !

        column  7 to 10

! -2.1189766   -2.2759378   -0.23544185   0.15696123  !

-->k = find( accy(1:$-1).*accy(2:$) < 0 )
                                !--error 144
Undefined operation for the given operands.

check or define function %c_x_c for overloading.

-->k = find( accy(1:$-1)*accy(2:$) < 0 )
                               !--error 144
Undefined operation for the given operands.

check or define function %c_m_c for overloading.

 

Only difference I spotted between real data and the test is that the test array doesnt begin and end wiht an exclamation mark. I've tried to convert accy to real numbers (in case they were complex for some reason) with

accy=real(accy) but that just gives another error message.

Anyone got any suggestions?

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