Day 128 of 180 Days of Data Viz Learning #jfdi

I’m doing some form of data visualization learning for 180 days because I need to #JFDI.

See post explaining how and why I’m doing this.

*Reading for these last precious few days before taking off for Christmas – where I’ll finish the Udacity course

Code Learning:

Learn JS Data Regular Expressions

  • Replacing with Regular Expressions
    • Example of replacing “wood” with the word “nun.”
      • var str = “how much wood would a woodchuck chuck if a woodchuck could chuck wood”;
      • var regex = /wood/g;
      • var newstr = str.replace(regex), “nun”
    • console.log(newstr);
      • => “How much nun would a nunchuck chuck if a nunchuck could chuck nun”
  • Finding Numbers
    • Extracting money from groceries as an example.  You’d need to define a regular expression that defines a patterns, for example in the below
    • Dollar sign as (\$) to indicate beginning of a price
    • Set of repeating characters than can be 0-9 or period(.) We denote these care appear repeatedly (+).
    • Word break to indicate end of the price string (\b)
    • var message = “I bought a loaf of bread for $3.99, some milk for $2.49 and” + “a box of chocolate cookies for $6.95”;
    • regex = /\$([0-9\.]+)\b/g;
    • matches = message.match(regex)console.log(matches);
    • =>  [“$3.99”, “$2.49”, “$6.95”]
  • Since we can’t add with $ signs, reduce!
    • matches.reduce(function(sum, value) {
    • return sum + Number(value.slice(1));
    • }, 0);
    • =>13.43
  • Using special characters
    • \d – any number character, equivalent to [0-9]
    • \D – any nonnumber character, equivalent to [^0-9]
    • \s – any single space character.  This includes a single space, tab, line feed or form feed.

 

 

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