Error: Values of BreakpointsForDimension1 in 'Lookup_table' must be monotonically increasing.

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I'm frustrated with the error that I'm getting while running my simulink model which has a 1-D lookup table. The lookup data is a nx1 matrix which is generated in an ODE45 integration. The error is:
Values of BreakpointsForDimension1 in 'output_control/Normal force' must be monotonically increasing.
I looked at other Q/As here but I couldn't understand them. Can someone please give me a workaround to this problem in an easy language so that a rookie in simulink like me can understand? I really appreciate it.
  1 Comment
Swarooph on 22 Jun 2017
Having the data and a simple model trying to use it will help us understand. Looks like a problem with dimensions of either data/breakpoints. But impossible to help without knowing more about the actual data.

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Answers (2)

Fangjun Jiang
Fangjun Jiang on 22 Jun 2017
The 1-D lookup table block has a parameter called "Breakpoints 1". It is a vector. The value needs to be incremental, for example [1, 1.1, 1.3]. If the value is not incremental, such as [1 2 2] or [1 3 2], the error message will appear.

babak znl
babak znl on 1 Jun 2018
hello I also had this problem but i found a solution. i used 2 lookup table instead of one , one lookup table for the incremental part and one for the decremental part, so you should separate your data from that break point from which error occurs , and you can use simple logic blocks to to direct the input data to the desired lookup table.


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