Change multiple values within a block by same amount

[Anonymous]

Morning,

Well I didn't know this place existed!!

So essentially I was wondering if there is a shortcut or LISP that would enable me to change multiple values by the same amount. 

The example is I want to drop a site by say 300mm therefore I want 100 values to drop by 0.3. I am trying to avoid doing this manually. I do want to be able to select the values to change, as not all will change, ie tie in points. Does anybody have any advice for me.

I have attached a dwg of the block.

Thanks in advance.

[3wood · Accepted solution]

You can try ALTEXT.

[hak_vz]

@3wood 

Will your programs make changes in case where some of @Anonymous  elevations have value like "102.5x" and other don't? Apply your code on whole sample and check left side where you can value like this.

[3wood]

Yes it works for a format as "102.5x".

[hak_vz]

@3wood

I asked this because I started writing a code after his request on Autocad forum. Since your solution works and OP is satisfied I don't have reasons to continue.