Count JSON Array Elements with jq

Sometimes when working with JSON on the command line, it is helpful to know how many elements exist in a JSON array. Fortunately this is easy to do with jq. jq is a lightweight, easy to use, command line JSON processor. *More information about jq can be found at https://stedolan.github.io/jq/manual/. Counting Array Elements in single

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Counting Relationships in Neo4j

When working with different graphs in Neo4j, it is often important to count the number of relationships between different nodes. Below are examples of common relationship counting tasks. The data for these examples can be found here and the script to load this data into Neo4j can be found here. Counting Total Relationships (Edges) MATCH

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How to Code a Recursive Fibonacci Sequence

A Fibonacci Sequence is a sequence of numbers in which the first and second numbers in the sequence are 0 and 1 respectively, and additional numbers in the sequence are calculated by adding the previous two. The first few numbers in the Fibonacci Sequence look like this: 0, 1, 1, 2, 3, 5, 8, 13,

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How to Code an Iterative Fibonacci Sequence

A Fibonacci Sequence is a sequence of numbers in which the first and second numbers in the sequence are 0 and 1 respectively, and additional numbers in the sequence are calculated by adding the previous two. The first few numbers in the Fibonacci Sequence look like this: 0, 1, 1, 2, 3, 5, 8, 13,

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How to Sum Array of Ints in Java

Aggregating data in an array is a common programming task. This can easily be done in Java by initializing a variable to hold the summed value, looping over the elements in the array, and adding these values to the total. The sumArray method below is a good example of how to sum the values in

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Count Unique Elements in Text File with AWK

Counting the distinct/unique elements of text file is a common task.  Below is an example of doing this is AWK, using sample_data_1.txt.

Here is what is happening above: cat sample_data_1.txt – reading the file piping the data to AWK BEGIN{FS=”\t”} – specifying the field separators of the file NR>1 – Only executing the following

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