Solution
You can access and modify data from your waveform chart history using a
property node as shown in this snippet:
You can create an
implicit or explicit property node to the waveform chart and then select
History Data.
By Right-clicking on the property node, you can choose between read or write by selecting
Change All To Read or
Change All To Write.
Using a property node in
write mode will allow you to modify the data whereas using a property node in
read mode will allow you to access the data.
As an example, this VI displays two charts, with a linear curve from 0 to 29. The first Waveform Chart history data is modified to replace the 15th data element by 0.
This is the result :