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Python 3 - How to create a typing effect in command line window

So I am having a slight problem.
I have this code:
def typingeffect(string):
string = list(string)
for i in string:
print(i, end="")
sleep(0.2)
typingeffect("Hello")
When I run this code through Python's (3.7) IDLE, it works as expected, putting one character after another with a delay of 0.2 seconds. However, when I run it through cmd.exe, it just prints it as one string.
It only works through command if I take out end="", in which case, it prints the letters with a delay on 0.2 seconds, but with a newline after each character resulting not in a typing effect, but with:
H
e
l
l
o
If anybody has a solution to why this is happening and how it can be fixed, I would be very grateful.
Thank you in advance.

You can use the flush parameter for print to always flush the output buffer after each call:
def typingeffect(string):
for i in string:
print(i, end="", flush=True)
sleep(0.2)
Otherwise flushes for standard output typically only occur for newlines.

The end=' ' option in print function in python

I tried running the following program:
for i in range(5):
print(i, end=' ')
However, it waits for me to write some string in the next line and gives the output like:
0 1 2 3 4 'Hi'
where 'Hi' is what I input. I'm using the latest version 3.6.5 and can't seem to understand the reason behind this error. Can anyone help?

The default value for end is '\n', meaning that print() will write a newline character after printing the arguments. This would put the cursor on the next line.
Usually, stdout (to which print() writes by default) is also line buffered, meaning that data written to it is not flushed (and shown on your terminal) until a newline character is seen, to signal the end of the line.
You replaced the newline with a space, so no newline is written; instead a space is written, letting you write successive numbers one after the other on the same line.
Add an extra, empty print() call after your for loop to write the newline after looping:
for i in range(5):
print(i, end=' ')
print()
You could also add flush=True to the print(..., end=' ') calls to explicitly flush the buffer.
Alternatively, for a small enough range(), pass in the values to print() as separate arguments, leaving end at the default. Separate arguments are separated by the sep argument, by default set to a space:
print(*range(5))
The * in front of the range() object tells Python to loop over the range() object and pass all values that produces as separate arguments to the print() call; so all 5 numbers are printed with spaces in between and a newline character at the end:
>>> print(*range(5))
0 1 2 3 4

How can I use \r to make Python print on the same line?

Can someone please thoroughly explain how a '\r' works in Python?
Why isn't the following code printing out anything on the screen?
#!/usr/bin/python
from time import sleep
for x in range(10000):
print "%d\r" % x,
sleep(1)

Your output is being buffered, so it doesn't show up immediately. By the time it does, it's being clobbered by the shell or interpreter prompt.
Solve this by flushing each time you print:
#!/usr/bin/python
from time import sleep
import sys
for x in range(10000):
print "%d\r" % x,
sys.stdout.flush()
sleep(1)

'\r' is just a another ASCII code character. By definition it is a CR or carriage return. It's the terminal or console being used that will determine how to interpret it. Windows and DOS systems usually expect every line to end in CR/LF ('\r\n') while Linux systems are usually just LF ('\n'), classic Mac was just CR ('\r'); but even on these individual systems you can usually tell your terminal emulator how to interpret CR and LF characters.
Historically (as a typewriter worked), LF bumped the cursor to the next line and CR brought it back to the first column.
To answer the question about why nothing is printing: remove the comma at the end of your print line.

Do this instead:
print "\r%d" % x,

This has nothing to do with \r. The problem is the trailing , in your print statement. It's trying to print the last value on the line, and the , is creating a tuple where the last value is empty. Lose the , and it'll work as intended.
Edit:
I'm not sure it's actually correct to say that it's creating a tuple, but either way that's the source of your problem.

How to print voltages side by side?

I'm using a program that prints out voltages one right below the other, like:
2.333
2.334
2.336
2.445
But I want it like:
2.333 2.334 2.336 2.445
Ok, here is what works for me:
while True:
voltsdiff = adc.readADCDifferential01(4096, 8)
import sys
print '{:.4f}'.format(voltsdiff),
sys.stdout.flush()

Just print them with a comma
print "%.4f" % (voltsdiff),
Moreover, you might want to use format method. You can read all about formatting here
print "{:.4f}".format(voltsdiff),
Lets say, you are printing these values by iterating a list, you can do something like this
data = [2.333, 2.334, 2.336, 2.445]
print " ".join(data)

As others have answered, to print output without a newline in Python 2, put a comma at the end of your print statement:
print "%.4f" % voltsdiff,
However, this will not flush the output, as standard output is line buffered by default (it will only be flushed when a newline is added to the output). There are a few ways you can fix that.
First, you could, at some point, append a newline with just a basic print statement, e.g.:
for i, voltsdiffs in enumerate(many_voltages):
print "%.4f" % voltsdiffs,
if i % 10 == 9:
print # puts a newline after every 10 values
Next, you could explicitly flush standard output, using sys.stdout.flush():
print "%.4f" % voltsdiffs,
sys.stdout.flush()
Finally, you can use the Python 3 style print function, which has a flush parameter (which does the flushing for you, if it is True):
# before any other code
from __future__ import print_function
# later
print(format(voltsdiffs, ".4f"), end=" ", flush=True)
I'd generally recommend the last version, as it's what you'll need to use in the future if you port your code to Python 3. It's also quite explicit, with each special characteristic of the printing (no newline at the end, flushing automatically) called for by a separate keyword argument.

If you print to terminal, you may use stdout with \r or \b escape
sys.stdout.write("\r%.4f\t%.4f\t%.4f\t%.4f" % (v1, v2, v3, v4))
The "\r" escape move the cursor at begining of line (like cr on same line) and "\b" is untab: move 4 position back.
P.S.:stdout do some cache, you should call sys.stdout.flush() to be sure that the result is on terminal at request, before the buffer is full

How can I edit a string that was printed to stdout?

How can I edit a string that I just printed? For example, for a countdown counter (First prints 30, then changes it to 29 and so on)
Thanks.

Print a carriage return \r and it will take the cursor back to the beginning on the line. Ensure you don't print a newline \n at the end, because you can't backtrack lines. This means you have have to do something like:
import time
import sys
sys.stdout.write('29 seconds remaining')
time.sleep(1)
sys.stdout.write('\r28 seconds remaining')
(As opposed to using print, which does add a newline to the end of what it writes to stdout.)

If you're targeting Unix/Linux then "curses" makes writing console programs really easy. It handles color, cursor positioning etc. Check out the python wrapper:
http://docs.python.org/library/curses.html

If you're on a xterm-like output device, the way you do this is by OVERWRITING the output. You have to ensure that when you write the number you end with a carriage-return (without a newline), which moves the cursor back to the start of the line without advancing to the next line. The next output you write will replace the current displayed number.

You can not change what you printed. What's printed is printed. But, like bradley.ayers said you can return to the beginning of the line and print something new over the old value.

You can use the readline module, which can also provide customized completion and command history.