Can I add message to the tqdm progressbar?

Question

The example shown in Usage of tqdm works well for me.

pbar = tqdm(["a", "b", "c", "d"])
for char in pbar:
    pbar.set_description("Processing %s" % char)

You can change the description to show a small message before the progress bar, like this:

from tqdm import trange
from time import sleep
t = trange(100, desc='Bar desc', leave=True)
for i in t:
    t.set_description("Bar desc (file %i)" % i)
    t.refresh() # to show immediately the update
    sleep(0.01)

/EDIT: in the latest releases of tqdm, you can use t.set_description("text", refresh=True) (which is the default) and remove t.refresh() (thanks to Daniel for the tip).

Other answers focus on dynamic description, but for a static description you can add a desc argument into the tqdm function.

from tqdm import tqdm

x = [5]*1000
for _ in tqdm(x, desc="Example"):
    pass
 
Example: 100%|██████████████████████████████████| 1000/1000 [00:00<00:00, 1838800.53it/s]

You can use set_postfix to add values directly to the bar.

Example:

from tqdm import tqdm
pbar = tqdm(["a", "b", "c", "d"])
num_vowels = 0
for ichar in pbar:
    if ichar in ['a','e','i','o','u']:
        num_vowels += 1
    pbar.set_postfix({'num_vowels': num_vowels})

The postfix dictionary is integrated into the progress bar:

100%|███████████| 4/4 [00:11<00:00,  2.93s/it, num_vowels=1]

Instead of a dictionary, you can use set_postfix_str to just add a string to the end of the progress bar.

I personally find it much cleaner to use the with statement:

from tqdm import tqdm

with tqdm(['a','b','c']) as t:
  for c in t:
    t.set_description(f'{c}')