Search 1D find element in which index

[Sam.Huang]

Hi all

  I have a demo want to search in 1D find element in which index,from numeric 1-10 when fill in numeric 3,5,6,7,10 can do it right excepted fill in numeric 1,2,4,8,9.What cause for the issue? Thanks for all prompt reply.

[altenbach · Accepted solution]

You are dealing with floating point values, so all equal comparisons are questionable. For example if ampltitude=2, the second peak has a value of 1.99999999999999956000 (if you display all decimal digits!) which is arguably not the same as 2. All Y values are the result of complicated calculations and will typically not fall into place unless you are very lucky.

Also:

• You don't need any local variables here. Makes no sense.
• You can stop the loop once the result is -1. No need to spin it an additional ~1000x times.
• Here's your code using more reasonable techniques (same result!)

[Sam.Huang]

Thanks for you,I got it.