CODEWITHSUNDEEP
javascriptfunction
Eric Miller
Eric Miller

Reputation: 47

no return from Javascript function

I wrote this script based on information I read here on Stack. It calls data from an API and is supposed to convert the directional degrees to cardinal. When I run it, I get no output. There is no error when I inspect the page. I found no syntax errors when I ran it through Fiddle.

I thought I could simply substitute a number (I tried 45) for num and get the script to run to no avail so I could use an expert eye. Thank you. 

var settings = {
  "url": "https://api.stormglass.io/v1/weather/point?lat=40.370181&lng=-73.934193&key=...",
  "method": "GET",
  "timeout": 0,
};

$.ajax(settings)
.fail(function(a,b,c) { console.log(a.responseJSON) })
.done(function(response) {
  console.log(response);

  variconwndr24 = function degToCompass(num) {
    var num = response.hours[17].windDirection[1].value;;
    while (num < 0) num += 360;
    while (num >= 360) num -= 360;
    val = Math.round((num - 11.25) / 22.5);
    arr = ["N", "NNE", "NE", "ENE", "E", "ESE", "SE",
      "SSE", "S", "SSW", "SW", "WSW", "W", "WNW", "NW", "NNW"
    ];
    return arr[Math.abs(val)];
  }
});

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>

Upvotes: 0

Views: 142

Answers (2)

Eddie D
Eddie D

Reputation: 1120

The main problem is in the callback function for done. You're defining a function degToCompass, but that function is never called. Additionally, you're re-defining a parameter for the function that you passed. No point in passing num as a parameter if you just overwrite it. Instead just pass response's desired value as the parameter. Also, for the sake of readability and maintenance, try breaking this up like this :

const arr = [
  "N", 
  "NNE", 
  "NE", 
  "ENE", 
  "E", 
  "ESE", 
  "SE",
  "SSE", 
  "S", 
  "SSW", 
  "SW", 
  "WSW", 
  "W", 
  "WNW", 
  "NW", 
  "NNW"
];

var settings = 
{
  "url": "https://api.stormglass.io/v1/weather/point?lat=40.370181&lng=-73.934193&key=...",
  "method": "GET",
  "timeout": 0,
};

function degToCompass(num) 
{
    while (num < 0) 
    {
      num += 360;
    }
      
    while (num >= 360) 
    {
      num -= 360;
    }

    val = Math.round((num - 11.25) / 22.5);
    return arr[Math.abs(val)];
}

function faiureCallback(a, b, c)
{
    console.log(a.responseJSON);
}

function doneCallback(response)
{
  // Do some stuff
  var num = response.hours[17].windDirection[1].value;;
  return degToCompass(num)
}

$.ajax(settings)
  .fail(faiureCallback)
  .done(doneCallback);

Upvotes: 0

TKoL
TKoL

Reputation: 13892

First off, try something like this instead:

var settings = {
  "url": "https://api.stormglass.io/v1/weather/point?lat=40.370181&lng=-73.934193&key=xdvfd",
  "method": "GET",
  "timeout": 0,
};

$.ajax(settings).done(function(response) {
  console.log(response);
  var degrees = response.hours[17].windDirection[1].value;
  variconwndr24 = degToCompass(degrees);
  console.log(variconwndr24);
  return variconwndr24;
});

function degToCompass(num) {
    while (num < 0) num += 360;
    while (num >= 360) num -= 360;
    val = Math.round((num - 11.25) / 22.5);
    arr = ["N", "NNE", "NE", "ENE", "E", "ESE", "SE",
      "SSE", "S", "SSW", "SW", "WSW", "W", "WNW", "NW", "NNW"
    ];
    console.log(arr[Math.abs(val)]);
    return arr[Math.abs(val)];
  }

In the way you did it, degToCompass never actually gets called, and the num argument becomes redundant because you immediately redefine it.

Upvotes: 2

Related Questions