Summary:
Scale height of 77 mesh objects, by a csv file column with 77 float values.
*iterate through csv column drop head and save row value to list.
*iterate through objects in collection and apply Z scale from respective csv column row

Hello,
I’m swirling now and can’t seem to lock in my code.
I am working on a data visualization map project and attempting to scale parts of a map in relation to a column of values in a csv file. I have 77 custom mesh objects in a collection and all of their origins are set to bottom surface center (for the purpose of scaling their height. Respectively, I have a csv file with column values with 77 rows. Each column has different stats, so I can change the index and get a different height map. I successfully can iterate over my csv file and see the correct values in a list.
Now, I’m having trouble iterating through my "77 objects" in my collection and assigning the correct row value to each object. I have looked at ‘[3pointedit][1]’ similar question, but it doesn’t address my specific workflow and I tried the code and I had trouble getting it to apply. I understand I have a counter in the ‘for loop’ I probably don’t need and maybe another variable holder, but I was just experimenting. If anyone has an idea, let me know! thanks!!!!

Here is my current (non-working) code. I don’t mind selecting all my collection objects before I run it, if that helps.

import bpy
import csv
import numpy as np

with open('csv_file') as csv_file:
readout = csv.reader(csv_file)

next(readout, None)


col_values = []
counter = 0

for row in readout:
    current_row_val = float(row[1])
    col_values.append(current_row_val)
    counter = counter + 1
    current_value = row[:]

    sel_objs = [obj for obj in bpy.context.selected_objects if obj.type == 'MESH']
    bpy.ops.object.select_all(action='DESELECT')

if sel_objs:
    obj1 = sel_objs.pop()
    obj1.select = True
    bpy.context.scene.objects.active = obj1
    bpy.ops.transform.resize(value=(1.0, 1.0, float(current_value), orient_type='GLOBAL', orient_matrix=((0.0, 0.0, 0.0), (0.0, 0.0, 0.0), (0.0, 0.0, 0.0)), orient_matrix_type='GLOBAL', constraint_axis=(False, False, False), mirror=False, use_proportional_edit=False, proportional_edit_falloff='SMOOTH', proportional_size=1.0, use_proportional_connected=False, use_proportional_projected=False, snap=False, snap_target='CLOSEST', snap_point=(0.0, 0.0, 0.0), snap_align=False, snap_normal=(0.0, 0.0, 0.0), gpencil_strokes=False, texture_space=False, remove_on_cancel=False, center_override=(0.0, 0.0, 0.0), release_confirm=False, use_accurate=False)

I updated my code. I get one object changing it’s scale, but not all respectively.

import bpy
import csv
import numpy as np

# **make sure to set csv file path**
with open('..../test_csv.csv') as csv_file:
    readout = csv.reader(csv_file)
    
    next(readout, None)
    

    col_values = []
    counter = 0
    
    for row in readout:
        current_row_val = float(row[1])
        col_values.append(current_row_val)
        counter = counter + 1
        current_value = row[:]
        #print(current_row_val)
        
    for object in bpy.context.selected_objects:
        bpy.context.object.scale[2] = ((col_values[1]) + 1) / 10

v03 Update. This code worked last night, but I may refine it based on user ‘thorst’ comments below.

import bpy
import csv
import numpy as np

# **make sure to set csv file path**
with open('..../test_csv.csv') as csv_file:
    readout = csv.reader(csv_file)
    
    next(readout, None)
    

    col_values = []
    #counter = 0
    
    for row in readout:
        #***************************^CHANGE_CSV_'column'row[]!
        current_row_val = float(row[2])
        col_values.append(current_row_val)
        #counter = counter + 1
        current_value = row[:]
        print(current_row_val)
        
    obj_counter = -1
    for active in bpy.context.selected_objects:
        obj_counter = obj_counter + 1
        bpy.context.view_layer.objects.active = active 
        
        # **Change the multiple divide value below, so the bars look better!
        
        # **FOR DATA BETWEEN 1000-100000 - sample 'Per Capita Income' INDEX 2!!!!!
        bpy.context.object.scale[2] = (col_values[obj_counter] / 7000) * 3

[My github repo for this test file][2]


  [1]: https://blender.stackexchange.com/questions/139160/how-to-use-csv-values-to-drive-object-scale
  [2]: https://github.com/gitgranthub/blender_scale_objects_csv.git

object_no = 0
for object in bpy.context.selected_objects:
    object.scale[2] = ((col_values[object_no]) + 1) / 10
    object_no += 1

for object in bpy.context.selected_objects: