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Check if key exists and iterate the JSON array using Python
...id_7"}"""
def getTargetIds(jsonData):
data = json.loads(jsonData)
if 'to' not in data:
raise ValueError("No target in given data")
if 'data' not in data['to']:
raise ValueError("No data for target")
for dest in data['to']['data']:
if 'id' not in dest:
...
Java default constructor
... you tell me which one of the following is a default constructor and what differentiates it from any other constructor?
13 ...
Which is better option to use for dividing an integer number by 2?
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Use the operation that best describes what you are trying to do.
If you are treating the number as a sequence of bits, use bitshift.
If you are treating it as a numerical value, use division.
Note that they are not exactly equivalent. They can give different results for negative integers...
Check whether a cell contains a substring
Is there an in-built function to check if a cell contains a given character/substring?
9 Answers
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Is this a “good enough” random algorithm; why isn't it used if it's faster?
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Your QuickRandom implementation hasn't really an uniform distribution. The frequencies are generally higher at the lower values while Math.random() has a more uniform distribution. Here's a SSCCE which shows that:
package com.stackoverflow.q14491966;
import java.util.Arrays...
Find the index of a dict within a list, by matching the dict's value
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tom_index = next((index for (index, d) in enumerate(lst) if d["name"] == "Tom"), None)
# 1
If you need to fetch repeatedly from name, you should index them by name (using a dictionary), this way get operations would be O(1) time. An idea:
def build_dict(seq, key):
return dic...
Show/hide 'div' using JavaScript
...// Show
element.style.display = 'inline-block'; // Show
Alternatively, if you would still like the element to occupy space (like if you were to hide a table cell), you could change the element's visibility property instead:
element.style.visibility = 'hidden'; // Hide
element.style.visibil...
How can I check if multiplying two numbers in Java will cause an overflow?
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If a and b are both positive then you can use:
if (a != 0 && b > Long.MAX_VALUE / a) {
// Overflow
}
If you need to deal with both positive and negative numbers then it's more complicated:
long maximum = Lo...
How to check size of a file using Bash?
...zes instead. I.e. file.txt is normally 100k; how to make a script check if it is less than 90k (including 0), and make it do wget a new copy because the file is corrupt in this case.
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Where is Java's Array indexOf?
...e are a couple of ways to accomplish this using the Arrays utility class.
If the array is not sorted and is not an array of primitives:
java.util.Arrays.asList(theArray).indexOf(o)
If the array is primitives and not sorted, one should use a solution offered by one of the other answers such as Ke...