General Document

General preconditions:

import sys
import ezdxf

try:
    doc = ezdxf.readfile("your_dxf_file.dxf")
except IOError:
    print(f'Not a DXF file or a generic I/O error.')
    sys.exit(1)
except ezdxf.DXFStructureError:
    print(f'Invalid or corrupted DXF file.')
    sys.exit(2)
msp = doc.modelspace()

This works well with DXF files from trusted sources like AutoCAD or BricsCAD, for loading DXF files with minor or major flaws look at the ezdxf.recover module.

Load DXF Files with Structure Errors

If you know the files you will process have most likely minor or major flaws, use the ezdxf.recover module:

import sys
from ezdxf import recover

try:  # low level structure repair:
    doc, auditor = recover.readfile(name)
except IOError:
    print(f'Not a DXF file or a generic I/O error.')
    sys.exit(1)
except ezdxf.DXFStructureError:
    print(f'Invalid or corrupted DXF file: {name}.')
    sys.exit(2)

# DXF file can still have unrecoverable errors, but this is maybe
# just a problem when saving the recovered DXF file.
if auditor.has_errors:
    print(f'Found unrecoverable errors in DXF file: {name}.')
    auditor.print_error_report()

For more loading scenarios follow the link: ezdxf.recover

Set/Get Header Variables

ezdxf has an interface to get and set HEADER variables:

doc.header['VarName'] = value
value = doc.header['VarName']

See also

HeaderSection and online documentation from Autodesk for available header variables.

Set DXF Drawing Units

Use this HEADER variables to setup the default units for CAD applications opening the DXF file. This settings are not relevant for ezdxf API calls, which are unitless for length values and coordinates and decimal degrees for angles (in most cases).

Sets drawing units:

$MEASUREMENT controls whether the current drawing uses imperial or metric hatch pattern and linetype files:

doc.header['$MEASUREMENT'] = 1

0

English

1

Metric

$LUNITS sets the linear units format for creating objects:

doc.header['$LUNITS'] = 2

1

Scientific

2

Decimal (default)

3

Engineering

4

Architectural

5

Fractional

$AUNITS set units format for angles:

doc.header['$AUNITS'] = 0

0

Decimal degrees

1

Degrees/minutes/seconds

2

Grad

3

Radians

$INSUNITS set default drawing units for AutoCAD DesignCenter blocks:

doc.header['$INSUNITS'] = 6

0

Unitless

1

Inches

2

Feet

3

Miles

4

Millimeters

5

Centimeters

6

Meters

7

Kilometers

8

Microinches

9

Mils

10

Yards

11

Angstroms

12

Nanometers

13

Microns

14

Decimeters

15

Decameters

16

Hectometers

17

Gigameters

18

Astronomical units

19

Light years

20

Parsecs

21

US Survey Feet

22

US Survey Inch

23

US Survey Yard

24

US Survey Mile

Create More Readable DXF Files (DXF Pretty Printer)

DXF files are plain text files, you can open this files with every text editor which handles bigger files. But it is not really easy to get quick the information you want.

Create a more readable HTML file (DXF Pretty Printer):

# on Windows
py -3 -m ezdxf.pp your_dxf_file.dxf

# on Linux/Mac
python3 -m ezdxf.pp your_dxf_file.dxf

This produces a HTML file your_dxf_file.html with a nicer layout than a plain DXF file and DXF handles as links between DXF entities, this simplifies the navigation between the DXF entities.

Changed in version 0.8.3: Since ezdxf v0.8.3, a script called dxfpp will be added to your Python script path:

usage: dxfpp [-h] [-o] [-r] [-x] [-l] FILE [FILE ...]

positional arguments:
  FILE             DXF files pretty print

optional arguments:
  -h, --help       show this help message and exit
  -o, --open       open generated HTML file with the default web browser
  -r, --raw        raw mode - just print tags, no DXF structure interpretation
  -x, --nocompile  don't compile points coordinates into single tags (only in
                   raw mode)
  -l, --legacy     legacy mode - reorders DXF point coordinates

Important

This does not render the graphical content of the DXF file to a HTML canvas element.

Set Initial View/Zoom for the Modelspace

To show an arbitrary location of the modelspace centered in the CAD application window, set the '*Active' VPORT to this location. The DXF attribute dxf.center defines the location in the modelspace, and the dxf.height specifies the area of the modelspace to view. Shortcut function:

doc.set_modelspace_vport(height=10, center=(10, 10))