Convert number to words - php

Question

How can I convert my amount into words? I tried this code but it gave me this error when I call the function.
Fatal error: Call to undefined function Convert()
Did I do something wrong?
if (isset($_REQUEST["generate"])) {
$amount=$_POST["amount"];
$amountinword=Convert($amount);
}
<?php
Class Convert {
var $words = array();
var $places = array();
var $amount_in_words;
var $decimal;
var $decimal_len;
function Convert($amount, $currency="Pesos") {
$this->assign();
$temp = (string)$amount;
$pos = strpos($temp,".");
if ($pos) {
$temp = substr($temp,0,$pos);
$this->decimal = strstr((string)$amount,".");
$this->decimal_len = strlen($this->decimal) - 2;
$this->decimal = substr($this->decimal,1,$this->decimal_len+1);
}
$len = strlen($temp)-1;
$ctr = 0;
$arr = array();
while ($len >= 0) {
if ($len >= 2) {
$arr[$ctr++] = substr($temp, $len-2, 3);
$len -= 3;
} else {
$arr[$ctr++] = substr($temp,0,$len+1);
$len = -1;
}
}
$str = "";
for ($i=count($arr)-1; $i>=0; $i--) {
$figure = $arr[$i];
$sub = array(); $temp="";
for ($y=0; $y<strlen(trim($figure)); $y++) {
$sub[$y] = substr($figure,$y,1);
}
$len = count($sub);
if ($len==3) {
if ($sub[0]!="0") {
$temp .= ((strlen($str)>0)?" ":"") . trim($this->words[$sub[0]]) . " Hundred";
}
$temp .= $this->processTen($sub[1], $sub[2]);
} elseif ($len==2) {
$temp .= $this->processTen($sub[0], $sub[1]);
} else {
$temp .= $words[$sub[0]];
}
if (strlen($temp)>0) {
$str .= $temp . $this->places[$i];
}
}
$str .= " " . $currency;
if ($this->decimal_len>0) {
$str .= " And " . $this->decimal . "/" . $this->denominator($this->decimal_len+1) . " Cents";
}
$this->amount_in_words = $str;
}
function denominator($x) {
$temp = "1";
for ($i=1; $i<=$x; $i++) {
$temp .= "0";
}
return $temp;
}
function display() {
echo $this->amount_in_words;
}
function processTen($sub1, $sub2) {
if ($sub1=="0") {
if ($sub2=="0") {
return "";
} else {
return $this->words[$sub2];
}
} elseif ($sub1!="1") {
if ($sub2!="0") {
return $this->words[$sub1."0"] . $this->words[$sub2];
} else {
return $this->words[$sub1 . $sub2];
}
} else {
if ($sub2=="0") {
return $this->words["10"];
} else {
return $this->words[$sub1 . $sub2];
}
}
}
function assign() {
$this->words["1"] = " One"; $this->words["2"] = " Two";
$this->words["3"] = " Three"; $this->words["4"] = " Four";
$this->words["5"] = " Five"; $this->words["6"] = " Six";
$this->words["7"] = " Seven"; $this->words["8"] = " Eight";
$this->words["9"] = " Nine";
$this->words["10"] = " Ten"; $this->words["11"] = " Eleven";
$this->words["12"] = " Twelve"; $this->words["13"] = " Thirten";
$this->words["14"] = " Fourten"; $this->words["15"] = " Fiften";
$this->words["16"] = " Sixten"; $this->words["17"] = " Seventen";
$this->words["18"] = " Eighten"; $this->words["19"] = " Nineten";
$this->words["20"] = " Twenty"; $this->words["30"] = " Thirty";
$this->words["40"] = " Forty"; $this->words["50"] = " Fifty";
$this->words["60"] = " Sixty"; $this->words["70"] = " Seventy";
$this->words["80"] = " Eighty"; $this->words["90"] = " Ninety";
$this->places[0] = ""; $this->places[1] = " Thousand";
$this->places[2] = " Million"; $this->places[3] = " Billion";
$this->places[4] = " Thrillion";
}
}
?>

Answer 1

Problem
You aren't creating an instance of Convert so PHP thinks it's a function.
Solution:
$convert = new Convert($amount);
$convert->display();
On a side note, your Convert method is acting as a constructor function. This is a backwards compatibility function from older versions of PHP. You should follow best-practices by renaming it to __construct now. From the manual:
Warning: Old style constructors are DEPRECATED in PHP 7.0, and will be removed in a future version. You should always use __construct() in new code.
Working example.
Also on a side note - you allow for the currency to be provided as an argument to the constructor method, so you should also allow for the decimal point name as well (Cents) - it's currently hard coded into your Convert method.