Script to import coordinates and create a bezier curve

Question

I would like to create a script to import coordinates from a CSV and create a bezier curve along these coordinates. I have developed a script that imports the coordinates, but it creates a curve along only one coordinate point. All remaining points are ignored and the curve always starts at the coordinate origin (0,0,0). Unfortunately I don't have a good knowledge of Phython. Therefore it would be great if someone could help me. Thanks a lot!

from mathutils import Vector 

import bpy
import csv, os, bmesh, math

#filepaths
filepath = bpy.data.filepath
directory = os.path.dirname(filepath)

verts = []
edges = []
faces = []

csvpoints= "NameofFilepath"
pointsReader = csv.reader(open(csvpoints, newline=''), delimiter=';')   
bpy.ops.curve.primitive_bezier_curve_add(enter_editmode=True)
with open(csvpoints, 'rt', encoding="utf8") as csvfile:
    pointsReader = csv.reader(csvfile, delimiter=';')
    for idx, row in enumerate(pointsReader):
        if (idx > 0):
            vert = (float(row[0]), float(row[1]), float(row[2])) 
            verts.append(vert)
            # Create curve and cache reference.
            curve = bpy.context.active_object
            bez_points = curve.data.splines[0].bezier_points
            bez_points = curve.data.splines[0].bezier_points

            # Set handles to desired handle type.
            for bez_point in bez_points:
                bez_point.handle_left_type = 'FREE'
                bez_point.handle_right_type = 'FREE'

                # Left point.
                bez_points[0].co = vert

[![Coordinates in CSV][1]][1]

Answer 1

Well, as you say your script just suffers from some little mistakes. Try this version:

import bpy, csv

csv_filepath= "<NameofFilepath>" # replace with a real path

# read all control points from csv file
with open(csv_filepath) as csv_file: # work with the opened file
    
    # first read the complete file (we need to know the amount of points)
    csv_reader = csv.reader(csv_file, delimiter=';')

    control_points = []
    for idx, row in enumerate(csv_reader):
        if idx != 0: # ignore csv header
            control_points.append((float(row[0]), float(row[1]), float(row[2])))
        
    # create bezier curve and add enough control points to it
    bpy.ops.curve.primitive_bezier_curve_add()
    curve = bpy.context.active_object
    bez_points = curve.data.splines[0].bezier_points

    # note: a created bezier curve has already 2 control points
    bez_points.add(len(control_points) - 2)

    # now copy the csv data
    for i in range(len(control_points)):        
        bez_points[i].co = control_points[i]
        bez_points[i].handle_left_type  = 'FREE'
        bez_points[i].handle_right_type = 'FREE'
               
        # just for illustration (screenshot),
        # add your correct handle locations here
        bez_points[i].handle_left  = control_points[i]
        bez_points[i].handle_right = control_points[i]

With this test csv file:

x;y;z;
1;0;0;
2;0;0;
2;1;0;
3;1;0;
3;1;1;
3;0;1;

i get this result:

It shows that the points from the file are set. Now you can go on and adjust handles, handle types ...