Print A Progress-bar Processing In Python

I wrote this simple function 'processing_flush' in order to print a sequence of points (given by index) to test if my software is processing my data and eventually the speed. The t

Solution 1:

Before you overwrite the same line again you need to clear at least the positions where the dots are with spaces.

def processing_flush(n, index=5):
    sys.stdout.write("\rProcessing %s" % (index * " "))
    sys.stdout.write("\rProcessing %s" % ((n % index)* "."))
    sys.stdout.flush()

The code above may lead to some brief flicker. In your specific case it is sufficient to clear the line when n % index becomes 0:

def processing_flush(n, index=5):
    if n % index == 0:
        sys.stdout.write("\rProcessing %s" % (index * " "))
    sys.stdout.write("\rProcessing %s" % ((n % index)* "."))
    sys.stdout.flush()

Or even better always write index-1 characters:

def processing_flush(n, index=5):
    sys.stdout.write("\rProcessing %s%s" % ((n % index)* ".", (index - 1 - (n % index))* " "))
    sys.stdout.flush()

Edit 1: Or if you prefer to have the cursor always after the last dot:

def processing_flush(n, index=5):
    sys.stdout.write("\rProcessing %s%s" % ((n % index)* ".", (index - 1 - (n % index))* " "))
    sys.stdout.write("\rProcessing %s" % ((n % index)* "."))
    sys.stdout.flush()

Edit 2: Or if you prefer to have the cursor always at the beginning of the line:

def processing_flush(n, index=5):
    sys.stdout.write("Processing %s%s\r" % ((n % index)* ".", (index - 1 - (n % index))* " "))
    sys.stdout.flush()

The reason is that your shell remembers the remaining characters of the previous line if you overwrite just the first part of it.