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// compactness() calculates how closely the resulting documents are located together
// It counts the size of the documents vs size of the unique pages they reside on
function compactness(collection, query, limit) {
Object.size = function(o) { var size = 0, key;
for (key in o) { if (o.hasOwnProperty(key)) size++; }
return size; };
count=0;
size=0;
import numpy as np
import scipy.optimize as spo
ir = lambda n: int(round(n))
# Constants
s_freq = 500 #server-server heartbeat frequency ms
c_freq = 10000 #client-server heartbeat frequency ms
# Simulation boundaries
threshold = 300000 # 5 minute max lag/skew
/*
* Auto-tuning delete that allows for removal of large amounts of data
* without impacting performance. Configurable to a target load amount.
*
* How it works:
* TL;DR: Delete a small slice every second; Vary the size of each slice
* based on how long the previous delete took; sleep; repeat.
*
* TODO: Modify this to allow for deletion based on objectid's date
* which is embedded in the first four bytes.
/* Check for gaps or duplicates in keyspace */
function check_keyspace(ns) {
print("Checking: " + ns);
str = JSON.stringify
forwardCount=0;
reverseCount=0;
min = db.chunks.find(ns).pretty().sort({min: 1}).limit(1)[0]
max = db.chunks.find(ns).pretty().sort({min:-1}).limit(1)[0]
current = min

Howdy folks

This is an attempt at standardizing the intro threads, and instructions on how to include a student map in them. Note the map & question set may be added to existing Piazza threads.

Steps:

Create a Google Map

  • Login to Google Maps, create a new Map
  • Menu -> Your Places -> Maps -> Create Map
"""
Vitter JS (1987) 'An efficient algorithm for sequential
random sampling.' ACM T. Math. Softw. 13(1): 58--67.
Copied from: https://gist.github.com/ldoddema/bb4ba2d4ad1b948a05e0
"""
from math import exp, log
import random
import numpy as np
//Create 1gb collection & enqueue
for(i=0;i<1000;i++){db.foo.insert({f:''.pad(1024*1024,true,'A')})}
enqueueWork("test.foo")
//Each worker calls dequeue() and works on it's own range
work = dequeue("test.foo")
function enqueueWork(ns,splitSizeBytes=320000000){
split = db.runCommand({splitVector:ns, keyPattern:{_id: 1},
import cv2
import os
#call visualize(QTable) tod display the qtable
#Press space to proceed, and q to exit (Frame render pauses execution)
def write(image, output_dir="visualize", name=None, is_test_image=False):
if not os.path.exists(output_dir):
os.makedirs(output_dir)
if name is None:
// compares MongoDB regular Indexes vs using MultiKey & Elematch
/* // regular index:
{ "field0": 0,
"field1": 1,
"field2": 2 ... etc }
MultiKey index:
{ "props": [
{ "field": "field0", "value": 0 },

Keybase proof

I hereby claim:

  • I am achille on github.
  • I am achille (https://keybase.io/achille) on keybase.
  • I have a public key whose fingerprint is 381B A447 5045 5140 AC05 46D2 A1D0 FF17 221A 89BF

To claim this, I am signing this object: