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April 15, 2014, 15:07 |
Expression =1 every 2 Timesteps
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#1 |
Member
Christian
Join Date: Sep 2013
Location: Germany
Posts: 88
Rep Power: 13 |
Hello,
im looking for an expression that is 1 every 2 timesteps. I tried to build the expression with a sin function but somehow it does not work propably. (abs(sin(Time*1[rad/s])) =1) is there a easier way? |
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April 15, 2014, 15:53 |
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#2 |
Senior Member
Edmund Singer P.E.
Join Date: Aug 2010
Location: Minneapolis, MN
Posts: 511
Rep Power: 21 |
Your way is close but you have the expression slightly wrong. And are you interested in every 2 "timesteps" or do you want this as a function of time?
For timesteps your variable needs to be ctstep not Time. Also, your sin function would need to be cos(ctstep*pi) in order to get it to "1" on every even step. But I would be afraid of roundoff error on this and wouldnt trust it to return true using a boolean to evaluate it, so I would switch to a step function. Perhaps: step(cos(ctstep*pi)-0.9) |
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April 15, 2014, 19:47 |
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#3 |
Super Moderator
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 17,870
Rep Power: 144 |
mod(cstep,2) is simpler and not prone to round off.
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April 17, 2014, 06:33 |
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#4 |
Member
Christian
Join Date: Sep 2013
Location: Germany
Posts: 88
Rep Power: 13 |
Thank you
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