Copy text to attribute while subtracting a value

[akark]

Hello,

Basically what I've been looking for and failed to find is this; I have tons of raw site elevation data in a drawing and I want to enter the datum into attribute blocks. While doing that I want to subtract my building's raw 0.00 value to find the relative elevation on a specific point with relation to my building. I have found numerous lisp routines to copy text into attributes but found none that adds/subtracts value while copying. 

[pbejse]

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@akark wrote:

Hello,

Basically what I've been looking for and failed to find is this; I have tons of raw site elevation data in a drawing and I want to enter the datum into attribute blocks. 

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What or where in the drawing is the source for the raw site elevation? 

The left side of the image does not have the 929 | 67 raw elevation data, is it part of the block?

[dbhunia · Accepted solution]

Hi,

What I got from your description & attached Image -

1   You should enter the datum value (say 929.00) into attribute blocks (that will be fixed value for the building).

2   At the time of Inserting Block you should select raw site elevation data (say 929.67) & pick Block Insertion Point.

3   After that Block will placed with the relative elevation of raw site elevation with relation to datum value.

If I an right then try the attached code.....

Only one thing you have to consider that, when you enter the datum value into attribute blocks that always keep integer/ float value (say 929 or 929.67), do not place any special character there (say + - ( )..etc.). otherwise code can not calculate the relative value.

It will give you your desired result (say 929.67(+0.67) or 929.67(+29.67) or 500.75(-399.25) etc.)

(defun c:CAT()
(setq Blk (getstring "\nEnter Block Name: "))
(while (setq entt (car (entsel "\nSelect Raw Elevation:")))
(setq enttx (entget entt))
(setq txt (cdr (assoc 1 enttx)))
(setq Ins (getpoint "\nPick/Enter Insertion Point: "))
(command "_.insert" blk ins "" "" "")
(setq elst1 (setq elst1 (entget (entnext (entlast)))))
(setq ff1 (assoc 1 elst1))
(setq Dat_Val (atof (cdr ff1)))
(if (> (- (atof txt) Dat_Val) 0)
(setq Att_text (strcat txt "(+" (rtos (- (atof txt) Dat_Val) 2 2) ")"))
(setq Att_text (strcat txt "(" (rtos (- (atof txt) Dat_Val) 2 2) ")"))
)
(setq xx (cons 1 Att_text))
(entmod (subst xx ff1 elst1))
(command "regen")
)
)

[akark]

Works like a charm, thanks a lot. 

Note for others using the code; the fixed elevation value is entered in the "default" line in attribute definition.