ImposedGroundMotion

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Jhno
Posts: 214
Joined: Sat May 05, 2012 2:55 pm
Location: Laval

ImposedGroundMotion

Post by Jhno » Sat Dec 16, 2017 7:19 am

Hi,
any1 has an explanation for the following? In both case, the timeseries is defined this way :

timeSeries Path 5 -time 0.025 -values 0.001

When I type in my analyze command this way :
for {set i 1} {$i<=4} {incr i 1} {
set okay [analyze 1 0.00625]
}
I get a 0.001 displacement after 4 iteration, as expected.
However, when I type it this way :
for {set i 1} {$i<=25} {incr i 1} {
set okay [analyze 1 0.001]
}
I do not get a 0.001 displacement after 25 steps, thought the command [getTime] does confirms the system time is at 0.025 s. I get something like 1e-12.
Any help on this? Thanks!

fmk
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Location: UC Berkeley
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Re: ImposedGroundMotion

Post by fmk » Fri Dec 22, 2017 11:10 am

it is probably roundoff .. .001 cannot be rep exactly and you might be getting .00100000000x or whatever and 25 times it is greater that .025 and so value in poath will be 0 .. use .0009999999

Jhno
Posts: 214
Joined: Sat May 05, 2012 2:55 pm
Location: Laval

Re: ImposedGroundMotion

Post by Jhno » Mon Jan 08, 2018 7:53 am

Aie, didn't think of this. Thanks!

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