shortdark/socket

Creates a date-based SVG graph from an array.

0.3.04 2022-04-08 12:29 UTC

README

Shortdark/Socket creates an SVG line graph from and array of up to 10 series of date-based data. This version currently assumes that the data will be from week days only, i.e. it expects not to have any data from weekends. Public holidays should be included in the array. Null values are not represented by a line, graph lines that contain null values will have gaps. More than 10 lines are possible on the graph if the extra line colors are specified manually.

Installation

$ composer require shortdark/socket

Basic Usage

<?php

require_once 'vendor/autoload.php';

$socket = new Shortdark\Socket;

$dataArray = [
    ['date'=>'2021-03-05', 'col1'=>116, 'col2'=> 156, 'col3'=>125],
    ['date'=>'2021-03-04', 'col1'=>115, 'col2'=> 155, 'col3'=>109],
    ['date'=>'2021-03-03', 'col1'=>114, 'col2'=> 154, 'col3'=>104],
    ['date'=>'2021-03-02', 'col1'=>113, 'col2'=> 153, 'col3'=>99],
    ['date'=>'2021-03-01', 'col1'=>112, 'col2'=> 152, 'col3'=>94],
    ['date'=>'2021-02-26', 'col1'=>111, 'col2'=> 151, 'col3'=>89]
];

$dataPointsArray = [
    ['date' => '2021-03-05', 'value' => 156, 'volume' => 1],
    ['date' => '2021-03-01', 'value' => 152, 'volume' => 2],
]; 

echo $socket->draw_svg($dataArray, $dataPointsArray);

Data Array

  • The graph can be empty (0 lines) or have up to 10 graph lines.
  • More than 10 graph lines can be passed in, but you would need to manually assign colors for the columns beyond the starting 10.
  • The number of lines is dependent on the data array that is passed in.
  • The columns must be named 'date', 'col1', 'col2', 'col3', 'col4', etc.
  • 'date' must be a string, format: '2021-02-26'.
  • The Y-axis data can be integers, floats or null.
  • Null values will not be shown on the graph.
  • The array should start with the newest date and work backwards.
  • It's assumed that the data will be continuous (mon-fri) without gaps in the data. Data can be 7 days a week, however, the week lines are currently on Friday.
  • Public holidays should also be included in the array with either the same value from the previous day, or with the value as null.

Representing A Range Of Values

If you have two lines that are the min and max values, and you want to represent them as a range on the graph, i.e. between the two lines is filled with color, you can make the filled_lines variable true.

  • Currently, it is either lines or ranges, not both.
  • Same naming convention as normal graph lines but the space between col1 and col2 would be filled, then the space between col3 and col4 would be filled, etc.
  • It expects an even number of lines with each pair getting filled. If col3 exists but col4 does not exist the line will not be shown.
  • The filled lines are semi-opaque so any ranges underneath are also visible.
  • The color used for each range is the color of the second line, i.e. col2, col4, col6, etc.

Data Points Array

  • Optional.
  • If the date of a data point is outside the date range of the graph it will be ignored.
  • Volume can be positive or negative, positive points are represented by a black circle, negative points are a red circle.

Optional Customization

Defaults are shown, below. Each of these variables can be altered, if desired.

  • width_of_svg INT (default: 1400)
  • height_of_svg INT (default: 540)
  • iterations INT (default: 10)
  • colors ARRAY (default ['col1' => 'dark green', 'col2' => 'medium blue', 'col3' => 'orange red', 'col4' => 'orange', ...])
  • show_week_numbers (default: false)
  • show_legend_box BOOL (default: true)
  • legend_box_width INT (default: 200)
  • legends ARRAY (default ['col1' => 'Column 1', 'col2' => 'Column 2', 'col3' => 'Column 3', 'col4' => 'Column 4', ...])
  • graph_name STRING (default: 'Key')
  • show_last_value_in_legend BOOL (default: false)
  • legend_pre_value STRING (default: '')
  • legend_post_value STRING (default: '')
  • branding_url STRING (default: '')
  • branding_text STRING (default: '')
  • brand_x_from_right INT (default: 120)
  • brand_y_from_bottom INT (default: 15)
  • filled_lines BOOL (default: false)
  • nearest_value BOOL (default: false)

You can modify any/all the above like so...

$socket = new Shortdark\Socket;

// Change the width of the SVG
$socket->width_of_svg = 1000;

// Change the height of the SVG
$socket->height_of_svg = 500;

// The number of horizontal lines
$socket->iterations = 10;

// The color of each line
$socket->colors = [
    'col1' => 'blue',
    'col2' => 'green',
    'col3' => 'orange',
    'col4' => 'red'
];

// Whether to show the week number from the start of the year (every fifth week: 5, 10...)
$socket->show_week_numbers = true;

// Optional, show a legends box to describe each graphline
$socket->show_legend_box = true;

// Optional, legends box, specify the width of the box
$socket->legend_box_width = 150;

// Give each graph line a label in the "legends box"
$socket->legends = [
    'col1' => 'This is column 1',
    'col2' => 'The second column',
    'col3' => 'Third',
    'col4' => 'Lastly... another'
];
$socket->graph_name = 'Something vs. Something else vs Another';
$socket->show_last_value_in_legend = true;
$socket->legend_pre_value = '&dollar;';
$socket->legend_post_value = '&#37;';

// The text/link in the bottom right hand corner
$socket->branding_text = 'Shortdark Web Dev';
$socket->branding_url = 'https://shortdark.co.uk';
$socket->brand_x_from_right = 0;
$socket->brand_y_from_bottom = 0;

// Representing two lines as a range, i.e. the space between the two lines is filled
$socket->filled_lines = false;

// Generally the graph starts/ends at a multiple of 10, the nearest value would be the nearest number above or below the max/min value.
$socket->nearest_value = false;

echo $socket->draw_svg($dataArray);

Author

Neil Ludlow - neil@shortdark.net - https://shortdark.co.uk