How to Skip Iterations in a Loop

GoTo Next Iteration in For Loop in java

continue;

continue; key word would start the next iteration upon invocation

For Example

for(int i= 0 ; i < 5; i++){
 if(i==2){
  continue;
 }
System.out.print(i);
}

This will print

0134

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See

• Document

How to skip iterations in a loop?

You are looking for continue.

Skip iteration in For loop and repeat initialisation in Python

The if statement is already skipping an iteration, so all you need is to repeat the initialization. You can do this by re-initializing the sum variable (a) inside the outer loop instead of outside.

A = [2, 4, 3, 1]
s = []

for i in range(len(A)):
    a = 0
    for j in range(len(A)):
        if i == j:
            continue
        else:
            a += A[j]
    s.append(a)

print(s)

Output:

[8, 6, 7, 9]

How to skip few iterations in a for loop based on a if condition?

Skipping 4 steps after each meeting condition ((i % 300) == 0) is equal to skipping 0, 1, 2, and 3. You can simply change the condition to skip all these steps with (i % 300) < 4.

for i in range(0, 200000):
    # (when 0 % 300 it meets this criteria) 
    if (i % 300) < 4: # Skips iteration when remainder satisfier condition            
    #if (i % 300) in (0,1,2,3): # or alternative skip condition
        # whenever this condition is met skip 4 iterations forward
        # now skip 4 iterations --- > (0, 1, 2, 3)
        continue

    # now continue from 4th iteration 
    print(i)

Skip iteration in loop if taking too long

You should run pd.read_sql in an another Thread, you can use this utility functions:

import time
from threading import Thread

class ThreadWithReturnValue(Thread):
    def __init__(self, group=None, target=None, name=None,
                 args=(), kwargs={}, Verbose=None):
        Thread.__init__(self, group, target, name, args, kwargs)
        self._return = None
    def run(self):
        print(type(self._target))
        if self._target is not None:
            self._return = self._target(*self._args,
                                                **self._kwargs)
    def join(self, *args):
        Thread.join(self, *args)
        return self._return

def call(f, *args, timeout = 5, **kwargs):
    i = 0
    t = ThreadWithReturnValue(target=f, args=args, kwargs=kwargs)
    t.daemon = True
    t.start()
    while True:
        if not t.is_alive():
            break
        if timeout == i:
            print("timeout")
            return
        time.sleep(1)
        i += 1
    return t.join()

def read_sql(a,b,c, sql="", con=""):
    print(a, b, c, sql, con)
    t = 10
    while t > 0:
        # print("t=", t)
        time.sleep(1)
        t -= 1
    return "read_sql return value"

conn = "conn"
t = "t"
print(call(read_sql, "a", "b", "c", timeout=10, sql=f''' select * from [DB].[SCHEMA].[{t}] ''', con=conn))

I got help from this answer.

by those functions:

for t in tablelist:
    df = call(pd.read_sql, timeout=yourTimeOutInSeconds , sql=f''' select * from [DB].[SCHEMA].[{t}] ''', con=conn)
    if df:
        df.to_csv(path, index=None)

Skip multiple iterations in a loop

I'd iterate over iter(z), using islice to send unwanted elements into oblivion... ex;

from itertools import islice
z = iter([1, 2, 3, 4, 5, 6, 7, 8])

for el in z:
    print(el)
    if el == 4:
        _ = list(islice(z, 3))  # Skip the next 3 iterations.

# 1
# 2
# 3
# 4
# 8

Optimization
If you're skipping maaaaaaany iterations, then at that point listifying the result will become memory inefficient. Try iteratively consuming z:

for el in z:
    print(el)
    if el == 4:
        for _ in xrange(3):  # Skip the next 3 iterations.
            next(z)

Thanks to @Netwave for the suggestion.

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If you want the index too, consider wrapping iter around an enumerate(z) call (for python2.7.... for python-3.x, the iter is not needed).

z = iter(enumerate([1, 2, 3, 4, 5, 6, 7, 8]))
for (idx, el) in z:
    print(el)
    if el == 4:
        _ = list(islice(z, 3))  # Skip the next 3 iterations.

# 1
# 2
# 3
# 4
# 8

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